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 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 01326, PSA Cloth Disc 348D, P240 X-weight, 3 in x NH, Die 300V, 7000045069
3M 31663, Cubitron II Net Disc 80+/180+/320+, includes 6 in discs and sheets, Job Pack, 7100251881, 100 Packs/Case
3M 22407, Roloc Disc 361F, 80 YF-weight, TR, 1-1/2 in, Die R150S, 7000045099
3M 26137, PPS Series 2.0 Adapter, Type S41, Trapezoidal Thread - QCC, 7100135947
3M 26141, PPS Series 2.0 Adapter, Type S44, 3/8 Female, 19 Thread BSP, 7100158892
3M 35083, EMI Copper Foil Shielding Tape 1181, 1/4 in x 18 yd (6,35 mm x 16,5 m), 7000132168
3M 37024, Extra Large Drywall Sanding Sponge 910-DDA, Dual Angle, 2-1/2 in x 8 in x 1 in, Fine, 7010375249 
