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?).

Dynabrade 53270 7" (180 mm) Dia. Right-Angle Disc Sander
Insize 2197, LARGE RANGE DIGITAL RADIUS GAGE, R1(4-590"/100-1500mm), R2(4-590"/100-1500mm), 697409778087
3M 26120, PPS Series 2.0 Adapter, Type S28, 17.5 mm Female, 19 TPI
Thread, 7100135956
3M 26116, PPS Series 2.0 Adapter, Type S25, 1/4 Female, 19 Thread BSP, 7100135957
3M 26054, PPS Series 2.0 Adapter, Type S18, 3/8 Female, 18 Thread NPS,
4 per case 