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 33443, Cubitron II File Belt, 36+, 1/2 in x 18 in (12.7 mm x 457.2 mm), 7100033184, 10 belts per carton, 5 cartons per case
3M 26137, PPS Series 2.0 Adapter, Type S41, Trapezoidal Thread - QCC, 7100135947
3M 26120, PPS Series 2.0 Adapter, Type S28, 17.5 mm Female, 19 TPI
Thread, 7100135956
Insize ISM-POL1000, POLARIZING MICROSCOPE, 6940561935790
3M 77512, Cloth Belt 777F, 60 YF-weight, 1 in x 42 in, Film-lok, Single-flex, 7010307736, 200 per case 