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Blue Fireball T Thread Spacer Ring with 4.5mm Extension # S-T4.5

4.8 (43 Reviews) Read Reviews Write Review
Brand Blue Fireball
Part Number S-T4.5
Availability available

Product Info

Manufacturer Description

Description/Uses:

  • T/T2 thread extension ring/barrel spacer
  • Provides 0.18" (4.5mm) of spacing *
  • Allows you to securely set or vary the spacing between T thread components
  • Has standard T threads (male on one side and female on the other)

Features:

  • Precision machined from aluminum and black anodized

Specifications:

  • Total Length = 0.4" (6mm)
  • Extension Provided = 0.18" (4.5mm) *
  • Length of External Male Thread = 0.06" (1.5mm)
  • Thread Specification (External Thread) = M42x0.75 Male
  • Length of Internal Female Thread = 0.06" (1.6mm)
  • Thread Specification (Internal Thread) = M42x0.75 Female
  • Maximum Outer Diameter = 1.81" (46mm)
  • Weight = 0.1oz (3g)

Additional Information:

* To get a spacing of 4.5mm with this spacer, your accessory must fit completely into the female T thread of this adapter. The length of the female T thread is only 1.6mm. If your accessory has a male T thread longer than this, then it will not screw in fully and the extension provided will be greater than 4.5mm.

Reviews

4.8 (Based on 43 Reviews) 93% of reviewers recommended this product.
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    1. Guest

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      Review by Don
      1559794261
      Jun 5, 2019

      5.0 Perfect for what I needed

      Pros:

      Cons:

      Comments:

      Perfect for what I needed

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    2. Guest

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      Review by PIETER
      1558538277
      May 22, 2019

      5.0 Fireball spacer

      Pros:

      Cons:

      Comments:

      Just what I needed, fits fine.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    3. Guest

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      Review by Jerome A.
      1555599950
      Apr 18, 2019

      5.0 Great adapters/extensions

      Pros:

      Cons:

      Comments:

      I always keep coming back to Agena for their Blue Fireball line of adapters. They're consistently high quality and a good value. Plus, they have the widest assortment I've seen - seems like I can always find what I need.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    4. Guest

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      Review by Carol S.
      1543419288
      Nov 28, 2018

      5.0 of Blue Fireball T Thread Camera Adapter for Prime Focus Photography -

      Pros:

      Cons:

      Comments:

      Excellent machining and perfect fit with the 2" T/T2 thread adapter for prime focus photography. Another great product from Agena!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    5. Guest

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      Review by David S.
      1538250731
      Sep 29, 2018

      5.0 12 mm spacer

      Pros:

      Cons:

      Comments:

      Ordered Friday afternoon. Had it Monday morning. Worked great for achieving the proper spacing between my focal reducer and CCD.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    6. Guest

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      Review by Chris H.
      1532181692
      Jul 21, 2018

      5.0 Good quality at a good price

      Pros:

      Cons:

      Comments:

      I've used Blue Fireball spacers in the past - they're good quality and a good price. Threads are smooth and fit and finish are excellent. This one is no exception.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    7. Guest

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      Review by David D.
      1524752267
      Apr 26, 2018

      5.0 Very good value

      Pros:

      Cons:

      Comments:

      Industinguishable from components costing much more... great quality at a great price

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    8. Guest

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      Review by John O.
      1523135120
      Apr 7, 2018

      5.0 Blue FireBall Adapter Ring

      Pros:

      Cons:

      Comments:

      Seems to be well made, but haven't used it yet. Arrived very quickly in the mail, thanks!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    9. Guest

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      Review by Steven C.
      1522350780
      Mar 29, 2018

      5.0 Blue Fireball T Thread Spacer 12mm Extension

      Pros:

      Cons:

      Comments:

      This enabled me to achieve the correct backspace needed for my camera and FR/FF.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    10. Guest

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      Review by Frank K.
      1520694020
      Mar 10, 2018

      4.0 Does the job

      Pros:

      Cons:

      Comments:

      Does the job

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    11. Guest

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      Review by Christopher C.
      1517853574
      Feb 5, 2018

      5.0 High quality

      Pros:

      Cons:

      Comments:

      High quality

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    12. Guest

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      Review by Keith E.
      1516050438
      Jan 15, 2018

      5.0 Great product

      Pros:

      Cons:

      Comments:

      Good spacer. Well made.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    13. Guest

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      Review by Leonard H.
      1515227357
      Jan 6, 2018

      5.0 Solved a problem

      Pros:

      Cons:

      Comments:

      The challenge with purchasing new equipment is that it will have threads of a size different from the older unit. Thankfully Agena a huge range adapters to solve the fitment issues that we run into.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    14. Guest

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      Review by John G.
      1510278990
      Nov 9, 2017

      5.0 Just a spacer

      Pros:

      Cons:

      Comments:

      It’s a simple spacer ring. A little expensive.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    15. Guest

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      Review by Robert T.
      1501851782
      Aug 4, 2017

      5.0 Does the job

      Pros:

      Cons:

      Comments:

      Nice machining, smooth threads. Good for the intended purpose.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    16. Guest

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      Review by Ed G.
      1498335404
      Jun 24, 2017

      5.0 Fireball Spacer

      Pros:

      Cons:

      Comments:

      Excellent and works beautifully. One thing with these little spacers is to try not to overtighten. They tend to lock up.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    17. Guest

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      Review by Mitchell C.
      1489775492
      Mar 17, 2017

      5.0 Excellent product. Works as described.

      Pros:

      Cons:

      Comments:

      Excellent product. Works as described. Agena's Service is excellent.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    18. Guest

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      Review by Ed Magowan
      1488210885
      Feb 27, 2017

      5.0 Just what I needed

      Pros:

      Cons:

      Comments:

      Needed this to set the distance of my guide camera on an OAG. Works perfectly.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    19. Guest

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      Review by Rene T.
      1484227943
      Jan 12, 2017

      5.0 Excelent!!!

      Pros:

      Cons:

      Comments:

      Excelent!!!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    20. Guest

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      Review by Greg of Belpre, OH.
      1463356800
      May 15, 2016

      4.0 It spaces!

      Pros:

      Lightweight,Easy to Use,Strong Construction

      Cons:

      Comments:

      Maybe not the fanciest out there but they work.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    21. Guest

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      Review by Leonard of Prineville, OR.
      1458950400
      Mar 25, 2016

      5.0 Well made and a perfect fit

      Pros:

      Accurate,Lightweight,Easy to Use,Strong Construction

      Cons:

      Comments:

      This adapter extends a T-ring threaded assembly by 30mm. It is well made and works exactly as you would expect.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    22. Guest

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      Review by Justin of Los Angeles.
      1454630400
      Feb 4, 2016

      5.0 Great fit and finish

      Pros:

      Strong Construction,Well Machined

      Cons:

      Comments:

      I purchased this to use with a 2" to T-thread adapter on my 4" f/5 short tube refractor. This combination allows my DSLR and autoguide camera to focus without having a diagonal in the light path. The anodizing is well done with now flaws, and the threading is smooth, with a perfect fit. Most importantly, Agena are the only supplier of such an item that I could easily find.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    23. Guest

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      Review by Craig of New Zealand.
      1435363200
      Jun 26, 2015

      5.0 Good Quality Spacer

      Pros:

      Accurate,Strong Construction,Lightweight,Easy to Use

      Cons:

      Comments:

      I have quite a few Blue Fireball adapters and spacer and they are all of the same high quality. A lot of spacers are made from cheap aluminium with threads that strip and chip as soon as you use them. Blue Firebll are high quality with smooth threads.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    24. Guest

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      Review by tnut55 of Missouri City, TX.
      1427760000
      Mar 30, 2015

      1.0 Be Careful

      Pros:

      Cons:

      Comments:

      I needed a small amount of increased back focal length between a ccd camera frame and another adapter. This spacer did not work; not because of the spacing but because there was only 1 full thread on the male side of the spacer and that was not enough to engage the first thread on the camera body. There are only about 2 threads on the female side. In my case, both threaded ends could have had up to 6 full threads and still accomplished the 2mm spacing while adding strength to the connection. As it is, it cannot be used.

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    25. Wayne

      Wayne New Member

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      Review by wboeck of Omaha.
      1427587200
      Mar 28, 2015

      5.0 Excellent quality

      Pros:

      Lightweight,Accurate,Compact,Strong Construction

      Cons:

      Comments:

      Works good for providing spacing for astrophotography

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    26. Guest

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      Review by dukeja of OK.
      1424476800
      Feb 20, 2015

      4.0 Be careful with the thread length

      Pros:

      Avid Adventurer

      Cons:

      Avid Adventurer

      Comments:

      It is my fault that I didn't check the female thread length so that my mating component cannot thread in completely, which makes the spacing not correct. Be careful on that!

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    27. Jesús Muñoz

      Jesús Muñoz New Member

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      Review by Jose of Mexico.
      1422662400
      Jan 30, 2015

      5.0 Problem solver

      Pros:

      Easy to Use,Strong Construction

      Cons:

      Comments:

      This product solved my reducer to chip distance problem.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    28. Guest

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      Review by JB of LINY.
      1387756800
      Dec 22, 2013

      4.0 T-thread spacer ring

      Pros:

      Cons:

      Comments:

      I used this spacer ring to gain additional lenght for a field flattner. It is well made with solid construction.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    29. Guest

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      Review by copperneck of utah.
      1386892800
      Dec 12, 2013

      5.0 Great product

      Pros:

      Lightweight,Easy to Use,Accurate

      Cons:

      Comments:

      I puchased the 10mm ring to use as a spacer between Canon t ring and a GSO coma corrector. Works perfectly.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    30. Guest

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      Review by Dan of Gaithersburg, MD.
      1385769600
      Nov 29, 2013

      5.0 I have a growing collection of these

      Pros:

      Strong Construction,Easy to Use,Lightweight,Accurate

      Cons:

      Comments:

      These are simple enough. I needed some additional spacing to take up some backfocus between a focal reducer and my camera/filter wheel.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    31. Guest

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      Review by chuck of Julian, CA.
      1354320000
      Nov 30, 2012

      5.0 Right product, fast delivery

      Pros:

      High Quality In And Out

      Cons:

      None

      Comments:

      Needed a spacer for a new CCD camera. Agena has a good selection. Worked perfectely.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    32. Guest

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      Review by njherr of Spokane, WA.
      1348272000
      Sep 21, 2012

      4.0 Solid Spacer

      Pros:

      Cons:

      Comments:

      Solid construction, no complaints.

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    33. Guest

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      Review by Rolf of Geyserland Observatory, Rotorua, NZ.
      1341014400
      Jun 29, 2012

      5.0 I would buy this product again

      Pros:

      Cons:

      Comments:

      It does what it was designed to do. It is inexpensive and lends itself to a number of combinations for astro imaging. I really can't see where it could be improved upon!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    34. MAK7

      MAK7 New Member

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      Review by Brad of Phoenix.
      1330128000
      Feb 24, 2012

      5.0 Good product

      Pros:

      Accurate,Lightweight,Strong Construction

      Cons:

      Comments:

      The threads are perfect on both ends. That is the important part.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    35. Guest

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      Review by Dan Crowson of O'Fallon, MO.
      1330128000
      Feb 24, 2012

      5.0 Work as advertised but think think...

      Pros:

      Accurate,Easy to Use

      Cons:

      Comments:

      Agena seems to be the best place to order these spacer rings. I used them to get the correct spacing for a field flattener.

      One thing to note - think about how to reach your correct spacing before ordering. I ordered a large one and a small one. The issue I ran into was that the smaller rings have very little thread on them due to their size. I would have been better off buying (for example) a 7mm and an 8mm to reach 15mm instead of say a 13mm and a 2mm.

      I made this mistake the first time and Agena allowed me to swap out for the correct setup easily without any kind of hassle.

      I always recommend Agena Astro at our local astronomy club.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    36. Guest

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      Review by Gary of New Zealand.
      1320019200
      Oct 30, 2011

      5.0 One of those hard to find accessories

      Pros:

      Lightweight,Strong Construction,Compact,Simple,Easy to Use

      Cons:

      Comments:

      I needed a thin T spacer ring to assist with the use of an Off Axis Guider. The 7.5mm I already had was too long, but the Blue Fireball in 3mm and also 4.5mm fitted the requirement perfectly. Cost effective as well. Very happy.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    37. Guest

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      Review by WhistleStop Observatory of Ontario, Canada.
      1306627200
      May 28, 2011

      5.0 Best spacers on the market!

      Pros:

      Ideal,Accurate,Excellent construction

      Cons:

      Comments:

      I tried a lot of spacers from others but none matched the accuracy and construction of the Blue Fireball...highly recommended. Two thumbs up for Agenaastro.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    38. Guest

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      Review by Chuck of Alpharetta, GA.
      1272844800
      May 2, 2010

      5.0 [...]

      Pros:

      Accurate

      Cons:

      Comments:

      I needed T-thread spacers to achieve the correct separation between a field flattner/focal reducer and my CCD camera. The product descriptions were accurate and I got exactly what I needed.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    39. Guest

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      Review by Marty of Santa Monica, CA.
      1272758400
      May 1, 2010

      5.0 Excellent craftsmanship

      Pros:

      Accurate,Strong Construction,Compact

      Cons:

      Comments:

      I bought the 40mm spacer ring as an extension tube for astro photography (eyepiece projection) use. It works beautifully, it is a well crafted piece and since it is all black inside, there are no unwanted reflections.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    40. Guest

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      Review by joel of Indiana.
      1272672000
      Apr 30, 2010

      5.0 Best priced spacer

      Pros:

      Accurate,Compact,Strong Construction

      Cons:

      Comments:

      These spacers work well and are priced right, the least expensive I could find.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    41. Guest

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      Review by BDS of Calgary, Alberta, Canada.
      1249516800
      Aug 5, 2009

      5.0 Blue Fireball T Thread Spacers

      Pros:

      Strong Construction,Accurate,Compact

      Cons:

      Comments:

      Excellent quality in machining, fit and finish. Would definitely recommend these products to everyone!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    42. Guest

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      Review by BP of Lexington, SC.
      1245110400
      Jun 15, 2009

      4.0 Solid, but inaccurate

      Pros:

      Cons:

      Comments:

      I purchased this to gain proper spacing between the Baader MPCC and a CCD camera. The problem with this item is that although it is supposed to give 3mm spacing, such a narrow body does not allow the "male" threads of the MPCC to screw in all the way. Thus, in the end, the ring actually ends up extending the imaging distance by about 7mm. On the positive side, the finish of this piece is exceptional, the threads are smooth. I also purchased the 10mm and the 20mm versions, and am very pleased with them. So, the quality of this piece (and of all the Blue Fireball spacers that I bought) is great; just be aware that with the 3mm version, you will probably end up with more than 3mm of spacing unless what you are attaching has a very shallow male thread.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    43. Guest

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      Review by JR of Clayton, NC.
      1243728000
      May 30, 2009

      5.0 Good Folks to deal with

      Pros:

      Accurate

      Cons:

      Comments:

      Got the product I ordered and a reasonable price. Will order again.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

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