Celestron 9.25 f/10 with Metric Threads

Celestron 9.25 f/10 with Metric Threads

Bob's Knobs allow you to collimate your Celestron Schmidt-Cassedgrain or EdgeHD optics without tools.

Fits: Celestron 9.25” (23.5 cm) f/10 SCT versions with metric screw threads (CPC 925). Not for C9.25 with “Trifid” Faster or EdgeHD optics (see Item C below).

Knobs: Black oxide steel (black) or stainless steel (silver), 12 mm (1/2”) diameter

Threads: Black oxide or stainless steel


  1. Black Phillips factory collimation screws usually have metric threads, but some black Phillips screws have standard 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. These knobs sit inside the tall lip around the perimeter of the secondary, so they may be hard to grasp with two fingers. Adjustments can be made using a thumb or finger against the inside edge of the knob.
  3. If your telescope has the “Trifid” Fastar rotary cover, these knobs will not fit. See C9.25fst.
  4. The factory dust cover will fit normally with Bob's Knobs installed.
  5. If your telescope has a factory-installed plastic cap over the collimation screws, it 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.


Our price: $20.95

In Stock - Ships Same Business Day Before 4 PM

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