Bob's Knobs for Celestron C8 f/10 Secondary with Hyperstar and Metric Collimation Screw Threads

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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: C8hypBO
Fits: Celestron 8" (20 cm) f/10 SCT with metric collimation screws and Hyperstar option (second photo).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- These knobs are taller than our other metric knobs to compensate for the countersunk factory screws in the Hyperstar secondary.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
Other Information
- Country of Manufacture: United States
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: C8hypBO
Fits: Celestron 8" (20 cm) f/10 SCT with metric collimation screws and Hyperstar option (second photo).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- These knobs are taller than our other metric knobs to compensate for the countersunk factory screws in the Hyperstar secondary.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
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: C8hypBO
Fits: Celestron 8" (20 cm) f/10 SCT with metric collimation screws and Hyperstar option (second photo).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- These knobs are taller than our other metric knobs to compensate for the countersunk factory screws in the Hyperstar secondary.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
Other Information
- Country of Manufacture: United States

Bob's Knobs for Celestron C8 f/10 Secondary with Hyperstar and Metric Collimation Screw Threads
