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Bob's Knobs Celestron 8" SCT Collimation Knobs - Metric - Black Oxide - C8METBO


Bob's Knobs Celestron 8" SCT Metric Secondary
Collimation Knobs - Black Oxide

Bob's Knobs Celestron 8" SCT f/10 Collimation Knobs fit Celestron 8" (20 cm) f/10 made in 2005 or later with Black Phillips factory collimation screws that have metric threads (non-EdgeHD Fastar and SkyWatcher SCT).

  • Bob's Knobs are made from black, oxide steel and are 12 mm in diameter (1/2")
  • The threads are black, oxide steel
  • Metric knobs are required on most models with black Phillips factory collimation screws. There are only a few post-2005 scopes that have black Phillips collimation screws with standard threads
  • 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 installation of Bob's Knobs. No worries though, the cover is cosmetic only and will not affect functionality of the scope
  • If there are EdgeHD optics, you will need to get other knobs as these only work with metric Fastar versions