Magnetic-Base Indicator Holder Arm Type Flexible Base Height 1 15/16 in Base Length 1 7/8 in Base Size 1 7/8 in L x 1.625 in W x 1 15/16 in H Base Type Magnetic Base Width 1 5/8 in Compatible Indicator Mounts 3/8 in Holding Power 100 lbf Maximum Reach 15 in Step Type Flat Working Length of Post/Lower Arm 15 in Base Thread Size 1/4 in-20 Construction Cast Iron Includes Snug No Magnet Type On/Off Knob Screw Type Knob