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 53715 Housing for Model 13515; 3,400 RPM
3M 07054, General Purpose Sanding Sponge CP041-12-CC, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Medium, 7100101246
Standard Abrasives 592305,Quick Change Aluminum Oxide 2 Ply Disc, 60, TR, 1-1/2 in, 7010368061, 50 per case 