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?).

Dynabrade 77762 4-1/2" Dia. x 7/8" Center Hole, 40 Grit, Type 27, Ceramic DynaCut Flap Disc, 10/pack
3M 20911, PSA Cloth Disc 348D, 50 X-weight, 2 in x NH, Die 200P, 7000118871
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 
