Rings will fit tubes with an outer diameter of 5.39" - 5.51" (Approx. 137 - 140mm).
These telescope tube rings are high quality, cast-aluminum mounting rings that can be used for mounting telescope tubes on various mounts or on guidescope rails. All rings are hinged, felt-lined and have clamp-style rings for easy mounting or repositioning of the optical tube. Most rings have clamping knobs while a couple of size have clamping clips instead. Please see the photo for this product to determine whether it has a clamping knob or clip.
The base of the rings has a metric 6mm mounting thread. Gunmetal dark gray finish. If the outer diameter (OD) of the telescope is a little smaller than the inner diameter (ID) of the rings, you can shim the inside of rings with extra felt (not included). Price shown is for a set of 2 rings.