Bob's Knobs for Celestron C11 f/10 with Flat Secondary Housing and Standard Collimation Screw Threads # C11std

Collimate your Catadioptric or Newtonian reflector style telescopes without tools!

It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass again. Installation is a snap with the included instructions, and you can undo the modification at any time.

Part: C11std
Fits: Celestron 11" (28 cm) f/10 SCT versions (metal or carbon fiber tube) with flat secondary housing and standard collimation screw threads (not for CPC 1100 or EdgeHD).

Knobs: Black plastic, 16 mm (5/8") diameter
Threads: Black anodized aluminum alloy

Notes:
1. Silver factory collimation screws usually have standard threads, but some silver Phillips screws have metric threads. Our hints will help you determine which screws are on your telescope. Make sure the knob threads match the factory screw threads before installing the knobs.
2. The factory dust cover will fit normally with Bob's Knobs installed.
3. Celestron 11" SCTs manufactured prior to 2006 have standard collimation screw threads.