The A-810 friction lock control is similar to the A-800 control but with 1/4-28 threaded end (non-swiveling). With Teflon™ liner. Travel: 3-3/8". The 1-1/4" dia. solid knob is available in black or blue (blue knob has smooth profile, not FAA style). 1/2" panel thread. Lengths are measured from under panel nut to end of threaded shaft with knob pushed in.