Bobs Knobs - KNOBS FOR CELESTRON 9.25 inch (23.5 cm) f/10 SCT WITH METRIC COLLIMATION SCREW THREADS (CPC 925)

COLLIMATE YOUR SCHMIDT-CASSEGRAIN STYLE OR NEWTONIAN STYLE TELESCOPE WITHOUT TOOLS

It′s easy . . . just grab a Bob′s Knob and turn. You can even do it while looking
through the eyepiece on most scopes. And 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.

Fits: Celestron 9.25 inch (23.5 cm) f/10 SCT versions with metric M3 screw threads (CPC
925)

Knobs: Black-oxide steel, 12 mm (1/2 inch) diameter

Threads: Black-oxide steel

Note1: The factory dust cover will fit normally with Bob′s Knobs installed.

Note2: 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.

Note3: 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) no
writing inside the secondary housing (except for the serial number); and 2) most have silver
factory collimation screws. Do not use metric knobs on these telescopes.

Note4: A few non-CPC 9.25 inch scopes manufactured in 2006 have black Phillips factory
collimation screws that aren′t metric. If your scope′s secondary housing looks like
this, it requires knobs with standard threads.