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 01326, PSA Cloth Disc 348D, P240 X-weight, 3 in x NH, Die 300V, 7000045069
3M 77558, Cubitron II Hookit Cloth Disc 947A, 77558, 40+ to 120+, 6 in x NH, Die 600Z, 7100232737
Insize 4807, ANGLE GAGE SET, 6928640319341
3M 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093
Standard Abrasives 863110, A/O Unitized Wheel, 631, 2 in x 1/4 in x 1/4 in, 7000144629
3M 05689, Hookit Sanding Block Round, 1-1/4 in X 10-3/4, 7000119962
Dynabrade 78123 2" Dia., Course, NWN DynaBrite, TR Locking-Type Disc, 25/pack
3M 07056, Drywall Sanding Sponge CP-042, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101555 