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 709187, A/O Straight Cartridge Roll, 1/2 in x 1-1/2 in x 1/8 in 60, 7100085869
Insize 0010-A35, SOUND LEVEL METER, 35dB~130dB, 6974029777004
3M 92250, Extra Large Single Angle Sanding Sponge 910PSA-12-CC, 2-7/8 in x 8 in x 1 in Fine, 7100101547 