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 26022, PPS Series 2.0 Adapter, Type S12, 10 mm Male, 1.0 mm Thread, 7100135943
Insize 6300, MICROMETER STAND, 6928640307294
3M 20942, PSA Cloth Disc 348D, 80 X-weight, 3/4 in x NH, Die 75K, 7000118911
Dynabrade 95745 1/4" NPT Speed Regulator 