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 97419, Aluminum Foil Tape 3380, Silver, 48 mm x 45 m, 3.25 mil, 7000049613
3M 24049, Wetordry Cloth Disc 281W, P1000 YF-weight, 8 in x NH, Die 800JM, 7000045052
3M 22404, Roloc Disc 361F, 80 YF-weight, TR, 3 in, Die R300V, 7000045100
Insize 0131-A120, LIGHT METER, 0.01~19.99FC, 0.1~199.9FC, 1~1999FC, 10~19990FC, 0.1~199.9Lux, 1~1999Lux, 10~19990Lux, 100~199900Lux, 6974029776557
3M 07056, Drywall Sanding Sponge CP-042, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101555
3M 97421, Aluminum Foil Tape 3380, Silver, 72 mm x 45 m, 3.25 mil, 7010375681 