Bob's Knobs for Meade 10" f/10 SCT with Three-Screw Secondary Now there is no more tools needed to make collimation adjustments to your telescope! It's easy . . . just grab a Bob's Knob and turn. You can even collimate while looking through the eyepiece on most telescopes. What's more, you'll never drop that pesky little Allen wrench or screwdriver in the grass again. Installation is a snap with included instructions, and you can undo the modification at any time. Bob's Knobs KNOBM10 - Meade 10 f/10 SCT with Three-Screw Secondary Fits: All Meade 10 inch (25 cm) f/10 SCT versions with three screws on the secondary housing (2120, LX10, LX50, LX100, LX200) 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. Later Meade 10 inch (25 cm) telescopes have six screws on the secondary housing. These scopes require different knobs.