The F3ES20 extremely fine hex adjuster is manufactured from 18-8 series stainless. The extremely fine 0.20 mm per revolution thread precludes the use of taps to produce threaded mating parts for this series of screws. The M3.5-0.20 mm threaded sleeve is manufactured on a super precision CNC turning center using a single point threading tool. The adjuster knob is sold separately and has a hex socket to provide for easy assembly. The back end of the adjuster screw also has a socket hex to allow it to be used as a set-screw.