Bob's Knobs for Celestron C5 f/10 Secondary with Standard Collimation Screw Threads

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Special Note: The Celestron 5” SCT uses either standard 6-32 or metric M3 collimation screws. Allen and silver Phillips factory collimation screws have standard threads. Most black Phillips screws are metric.
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: C5std
Fits: Celestron 5" (13 cm) f/10 SCT (C5, NexStar 5) with black allen (see second photo above), silver Allen, or silver Phillips factory collimation screws. These screws have standard threads. Will not fit scopes with black Phillips factory collimation screws (for that, see Item C5met instead).
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Black anodized aluminum alloy
Notes:
- These knobs will fit all C5 models made prior to 2006, and all 2006 and later models EXCEPT those with black Phillips factory collimation screws. The black Phillips screw model requires C5 metric knobs (Item C5met). Check that our screw threads match the factory screw threads before installing.
- The factory dust cover will fit normally with Bob's Knobs installed.
- Some telescope versions have a small plastic cover over the factory collimation screws. This cover must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
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: C5std
Fits: Celestron 5" (13 cm) f/10 SCT (C5, NexStar 5) with black allen (see second photo above), silver Allen, or silver Phillips factory collimation screws. These screws have standard threads. Will not fit scopes with black Phillips factory collimation screws (for that, see Item C5met instead).
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Black anodized aluminum alloy
Notes:
- These knobs will fit all C5 models made prior to 2006, and all 2006 and later models EXCEPT those with black Phillips factory collimation screws. The black Phillips screw model requires C5 metric knobs (Item C5met). Check that our screw threads match the factory screw threads before installing.
- The factory dust cover will fit normally with Bob's Knobs installed.
- Some telescope versions have a small plastic cover over the factory collimation screws. This cover must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
Special Note: The Celestron 5” SCT uses either standard 6-32 or metric M3 collimation screws. Allen and silver Phillips factory collimation screws have standard threads. Most black Phillips screws are metric.
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: C5std
Fits: Celestron 5" (13 cm) f/10 SCT (C5, NexStar 5) with black allen (see second photo above), silver Allen, or silver Phillips factory collimation screws. These screws have standard threads. Will not fit scopes with black Phillips factory collimation screws (for that, see Item C5met instead).
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Black anodized aluminum alloy
Notes:
- These knobs will fit all C5 models made prior to 2006, and all 2006 and later models EXCEPT those with black Phillips factory collimation screws. The black Phillips screw model requires C5 metric knobs (Item C5met). Check that our screw threads match the factory screw threads before installing.
- The factory dust cover will fit normally with Bob's Knobs installed.
- Some telescope versions have a small plastic cover over the factory collimation screws. This cover must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
Other Information
- Country of Manufacture: United States
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Bob's Knobs for Celestron C5 f/10 Secondary with Standard Collimation Screw Threads


















