Our ring sets provide rigid mounting for astro-imaging with our 4" and 5" scopes. Bottom and top of each ring is drilled for ¼"-20 hardware, have bat-handle locks, and two Tele Vue accessory slots for ring-mounted accessories such as Starbeam with Tele Vue base, Sol-Searcher, Piggy-Cam and others.
Sets come with a top accessory bar, bottom mounting plate to allow spacing them 5.5" to 6.5" apart. The included bottom plate (BPL-1098) is drilled to mate to a variety of mounts or mounting adapter plates - including the Tele Vue/Vixen Mount Adapter (AVT-1011) and Tele Vue Gibraltar-5 Head.
For NP101/NP101is with outside tube diameter of exactly 4-inches.