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 37024, Extra Large Drywall Sanding Sponge 910-DDA, Dual Angle, 2-1/2 in x 8 in x 1 in, Fine, 7010375249
Insize 4807, ANGLE GAGE SET, 6928640319341
3M 26138, PPS Series 2.0 Adapter, Type S42, 3/8 Female R-Angle, 19Thread BSP, 7100135930
3M 03140, General Purpose Sanding Sponge CP041-6P, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Medium, 7100101537, 6/pack 