Bob's Knobs for Celestron C8 f/10 Pre-1980 Orange-Tube Secondary

Collimate your Schmidt Cassegrain Telescope without special tools when you use Bob's Knobs! It's easy: Just grab a Bob's Knob Collimation Thumbscrew and turn it. You can even do it while looking through the eyepiece on many scopes. 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 if you wish. The factory dust cover will fit normally with Bob's Knobs installed on your secondary.

• Installation is a snap with the included instructions
• Modification can be undone at any time
• Knobs are crafted from black plastic, black oxide steel (black) and/or stainless steel (silver)
• No tools required to perform a collimation!

These Bob's Knobs C8org collimation knobs fit the Pre-1980 Celestron 8” (20 cm) f/10 SCT with orange optical tube and factory set-style collimation screws.

1. These knobs will fit orange tube C8 models made prior to 1980. The secondary has factory set-style collimation screws with a fourth central screw in the secondary housing.
2. Note: Two sets of knobs, each with a different screw length, are included with your order. Use the length that fits your telescope best. There should be two or three screw thread turns above the secondary housing and the dust cover should fit without contacting the knobs.