Bob's Knobs for Celestron CPC925 Telescopes
Fits: Celestron 9.25 inch (23.5 cm) f/10 SCT versions with metric M3 screw threads (CPC 925). It is important that you choose the correct style Bob's Knobs for your telescope. Please note the number and type of screws on your secondary housing before ordering. The CPC 925 SCT requires knobs with metric threads. The CPC 925 secondary can be identified by 1) a factory-installed plastic cover over the collimation screws; 2) black Phillips factory collimation screws; and 3) brand information on the inside of the housing, as shown on the above photo.
The secondary housing cover will still fit when Bob's Knobs are installed, but can be left off if desired. The cover is cosmetic only and will not affect operation of the scope. Celestron 9.25 inch SCTs manufactured prior to 2006 have standard 6-32 collimation screws and require knobs with standard threads. These telescopes can be identified by 1) silver factory collimation screws; and 2) no writing inside the secondary housing (except for the serial number). Do not use metric knobs on these telescopes.