The 9376 0.38 inch (9.6 mm) Adjustment Screw provides smooth, wobble-free adjustment combined with exceptional long-term stability and low susceptibility to thermal variation. It is the same 1/4-100 precision screw used in our optic mounts and allows you to build your own mounts or positioners. In addition to a travel of 0.38 inch (9.6 mm); the screw has a ball tip, unbraked brass bushing, and is knob adjusted.