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?).

Dynabrade 15336 Rubber Drive Wheel
3M 66654, Cloth Belt 340D, P220 X-weight, 37 in x 60 in, Film-lok, Single-flex, 7010300097, 5 per case 
