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 26135, PPS Series 2.0 Adapter, Type S40, Trapezoidal Thread, 7100135335
Norton 66261014793 - 3" Medium Grade Aluminum Oxide Bear-Tex Speed-Lok High Strength Maroon TR Non-Woven Abrasive Disc, 80 Each
Norton 66254497067 - 2" X 1/4" 100 - 150 Grit Medium Grade Aluminum Oxide Vortex Rapid Blend Blue TR Non-Woven Abrasive Disc, 25 Each
3M 77197, Scotch-Brite™ Roloc™ Deburr and Finish PRO Unitized Wheel,TR, 3 in x 1/8 in x NH, 8C CRS+, 7100109130, 40/box
3M 45025, Diamond Grade DG3 Reflective Digital Sheeting 4084UDS, Fluorescent Orange, 36 in x 50 yd, 1 Roll/Case, 7100282391
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
3M 76540, Cloth Belt 461F, P60 YF-weight, 57 in x 126 in, Film-lok, Full-flex, 7100218673, 40 per case
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 