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 54763, SandBlaster Right Angle Grinder Multi-Layer Disc, 4 1/2 in 36g 9678, 7010384119
Norton 66261014921 - 2" X 1/8" 50 - 80 Grit Coarse Grade Aluminum Oxide Bear-Tex Speed-Lok Rapid Blend Gray TR Non-Woven Unified Wheel, 60 Each
3M 26015, PPS Series 2.0 Adapter, Type S8, 12 mm Male, 1.0 mm Thread, 7100135931
Standard Abrasives 877041, Unitized Mounted Point, 731 W163 x 1/8 in, 3M 7010301192
3M 97421, Aluminum Foil Tape 3380, Silver, 72 mm x 45 m, 3.25 mil, 7010375681
3M 26104, PPS Series 2.0 Adapter, Type S20, 1/8 Male, 27 Thread NPSM, 7100135929
3M 05009, Utility Cloth Roll 211K, 100 J-weight, 1 in x 50 yd, Full-flex, 7100016843
3M 22409, Roloc Disc 361F, P120 XF-weight, TR, 1-1/2 in, Die R150S, 7000045103
3M 03126, General Purpose Sanding Sponge CP040-6P, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101532, 6/pack 