Spindle-Mounted Indicator Holder Arm, Arm Type Articulating, Base Height 17/50 in, Base Length 40 mm, Base Size 40 mm L x 8 mm W x H, Base Type Magnetic, Base Width 8 mm, Compatible Indicator Mounts 6 mm, Fine Adjustment Position Fine Adjust Top (FAT), Maximum Reach 178 mm, Working Length of Post/Lower Arm 56 mm, Working Length of Snug/Third Arm 71 mm, Working Length of Upper Arm 51 mm, Base Thread Size M8 x 1.25, Construction Steel, Includes Zinc Cast Fine Adjustment, Includes Snug Yes