Accuracy: ?2″.
To inspect protractor, taper gage, index plate, index head and goniometer, can also be used to set angle.
Made of special alloy steel, hardness HRC64, high stability, wear resistance and easy combination.
Can be combined to any angle with interval 6 seconds after combination (6″, 12″, 18″, … , 360?).

3M 26116, PPS Series 2.0 Adapter, Type S25, 1/4 Female, 19 Thread BSP, 7100135957
Dynabrade 52775 3/8" Reversible Drill, .5 HP, Rear Exhaust, 1,800 RPM
3M 35083, EMI Copper Foil Shielding Tape 1181, 1/4 in x 18 yd (6,35 mm x 16,5 m), 7000132168
Insize 2197, LARGE RANGE DIGITAL RADIUS GAGE, R1(4-590"/100-1500mm), R2(4-590"/100-1500mm), 697409778087 