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 06471, Cut & Grind Wheel, Type 27, 9 in x 1/8 in x 7/8 in, 7100219186, 20 per case
Insize 4168-3E, STEEL STANDARD BALLS, 5/32", 6940561981414
3M 05068, Cubitron II Stikit Film Disc 775L, 400+, 5 in x NH, Linered w/Tab, Die 500X, 7100145364, 250 per case
3M 26006, PPS Series 2.0 Adapter, Type S5, 12 mm Male, 1.5 mm Thread, 7100135831 