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
3M 45019, Diamond Grade DG3 Reflective Digital Sheeting 4081UDS, Fluorescent Yellow, 36 in x 50 yd, 1 Roll/Case, 7100282389
3M 07054, General Purpose Sanding Sponge CP-041-ESF, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Medium, 7100101551 