Bob's Knobs for FPI Protostar Secondary (8-32 collimation screw)
We offer knobs for the FPI Protostar secondary that has either 8-32 or 10-24 collimation screws. FPI Protostar secondary assemblies are used in several different Newtonian designs. Select knobs for your secondary from the list below.
A. Knobs for FPI Protostar Secondary (8-32 collimation screw)
Fits: FPI Protostar secondary assemblies using a 8-32 x 1 inch long set screw for collimation adjustment
Knobs: Black plastic, 13 mm (1/2”) diameter
Threads: Stainless steel
- These knobs will fit the FPI Protostar secondary assemblies with 8-32 x 1 inch long set-style collimation screws. The outside edge of each knob is slightly in the light path.