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 79808 DynaBolt AO 4" x .035" x 3/8" T1 Cut-off Wheel, Box of 10 Discs
Insize ISY-700-90024, SQUARE SUPPORT, 6940561980820
3M 16023, PPS Cup & Collar, Large, 7000000642
3M 92250, Extra Large Single Angle Sanding Sponge 910PSA-12-CC, 2-7/8 in x 8 in x 1 in Fine, 7100101547 