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 27551, EMI Copper Foil Shielding Tape 1181, 1/2 in x 18 yd (12.70 mm x 16.5m), 7000132182
Insize 0010-A35, SOUND LEVEL METER, 35dB~130dB, 6974029777004
3M 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093
Dynabrade 15420 Dynafile III Abrasive Belt Tool
3M 91004, Drywall Sanding Sponge CP-042-4PK, Single Angle, 4-7/8 in x 2-7/8 in x 1 in, Fine, 7100111452, 4/pack 