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 19771, Utility Cloth Sheet 314D, 9 in x 11 in P100 J-weight, 7000021272
3M 20897, PSA Cloth Disc 348D, 80 X-weight, 4 in x NH, Die 400BB, 7010294664
Insize 1120-150A, ELECTRONIC INSIDE GROOVE CALIPER, 22-150mm, 6928640302220
Dynabrade 78598 3/8" Dia. x 2" W x 1/8" Center Hole, 60 Grit, 100/pack
3M 33446, Cubitron II File Belt, 80+, 1/2 in x 18 in (12.7 mm x 457.2 mm), 7100033186, 10 belts per carton, 5 cartons per case
3M 28126, Hookit Clean Sanding Disc 900DZ, 5 in 80 J-weight, Die 500LG, 7010290258
3M 22397, Roloc Disc 361F, 60 YF-weight, TR, 1-1/2 in x NH, 7000045097
Dynabrade 91166 1/2" W x 13" L 80 Grit A/O DynaCut Belt, 50/pack
Dynabrade 97568 3/8" NPT Female Safety Coupler 