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?).

Standard Abrasives 712644, A/O Tapered Cone Point, K-110 180, 7100166526, 100 per case
3M 44495, Diamond Grade DG3 Reflective Digital Sheeting 4091UDS,Yellow, 48 in x 50 yd, 1 Roll/Case, 7100273873
Dynabrade 98263 3/8" NPT Male Plug 