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Bob's Knobs Celestron 8" SCT Collimation Knobs Secondary - C8STD

SKU: BOB-C8STD

Bob's Knobs Celestron 8" SCT Collimation Knobs Secondary

Bob's Knobs Celestron 8" SCT f/10 Collimation Knobs fit Celestron 8" (20 cm) f/10 post-1980 SCT with factory silver or Allen Phillips collimation screws, with or without Fastar secondary with silver collimation screws (NexStar 8, Ultima 2000, C8 black, or gray, etc). Please note that this includes post-2000 orange tube but does not fit pre-1980 orange tube or majority of scopes with black Phillips factory collimation scews.

  • Bob's Knobs are made from black plastic and are 13 mm in diameter
  • The threads are black, anodized aluminum alloy
  • C8 metric knobs are required on most models with black Phillips factory collimation screws
  • Spacers are required for knobs installed on the Fastar secondary with silver collimation screws for proper clearance. Bob's Knobs provides spacers in order to raise the knobs slightly for easier use. If the knobs contact the inside of the full-aperture dust cove the spacers can be omitted
  • There may be a small plastic cover over the factory collimation screw on some telescope versions. This cover will need to be removed and set aside with the intallation of Bob's Knobs. No worries though, the cover is cosmetic only and will not affect functionality of the scope