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 27706, Cubitron II Roloc Durable Edge Disc 984F, 36+, YF-weight, TSM, Maroon, 3 in, Die RS300VM, 7000045170, 200 per case
3M 45019, Diamond Grade DG3 Reflective Digital Sheeting 4081UDS, Fluorescent Yellow, 36 in x 50 yd, 1 Roll/Case, 7100282389
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
3M 76790, Roloc Disc 361F, 60 YF-weight, TS, 2 in, Die RS200P, 7010300088
Dynabrade 90873 2" Dia. Medium NWN DynaBrite Locking-Type Disc, 25/pack
3M 17085, Versaflo Hood with Integrated Head Suspension, S-433S-5, Small/Medium, 7000127431, 5 EA/Case
Dynabrade 98270 1/2" Male Coupler 