Starrett 657F Swivel Post Assembly for Magnetic Base Indicator Holder

Swivel cap (B) slot permits 90 degree post travel to horizontal position and post (C) rotates 360 degree (G) step diameter 7/32", 1/2" long Upper arm (F) is 2" long with a 5/16" diameter and swings more than 180 degree friction joint holds it in position Fine-adjusting screw (E): turn to zero set indicator