William Optics 2" Quartz Dielectric Coating Diagonal for Refractors

If what you are looking for is the highest achievable brightness, contrast and sharpness during critical observations with high-end instruments, WO 90° 2" mirror Quartz Dielectric star Diagonal is your choice. We recommend this product for everyone who only wants the best.

Top-Notch Performance and Brightness
• Dielectric coating allows 99% reflectivity.
• 10mm thick substrate flat for optimal image stability
• Quartz being a harder material, it can be polished to a higher accuracy. Quartz also boasts one of the lowest expansion rate compared to other materials.
• Accurate design guarantees constant alignment. No further alignment needed.

Meticulous Craftsmanship
• 2" to 1.25" eyepiece adapter included.
• Lock screw for eyepiece/adapter.
• Big, knurled thumbscrews easy to turn even with gloves on.

Strikingly Beautiful
• Patented, elegant design.
• High-quality machining out of the best aluminum.
• Internally antireflection threaded for highest contrast.

Superbly Constructed
• Compression rings (both on diagonal and adapter) to prevent barrels-marring.
• Internal safety stop prevents 2" barrels from hitting the mirror.

Why W.O. diagonals do not feature an Adjustable alignment system?
Having an adjustable alignment system is an admission that the diagonal can go out of collimation due to poor mechanical construction. Thanks to the patented design of WO diagonals, you will always have a diagonal that performs perfectly like the first day you got one!

Features:
• Ultra High Dielectric 99% reflectivity
• Highest precision surface with 10mm-thick mirror.
• 2"- 1.25" adapter with brass clamping ring.
• Inside diameter (48mm): threaded to fit a variety of filters.
• Weight: 470 g