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 5677, DISC PAD HOLDER 914, 4 IN X 1/8 IN X 3/8 IN M14-2.0 INTERNAL, 7010299278
3M 52753, Head Harness Assembly 7581, System Component, 7000002157, 20 EA/Case
3M 77737, ROLOC DISC PAD TS AND TSM, EXTRA HARD, 3 IN 1/4-20 INTERNAL, 7010299209
3M 13627, 947, Hookit Disc Pad Holder, 7 in x 1 in x 5/8 in 5/8-11 Internal, 7000028353
3M 45100, Roloc Disc Pad TR, Hard 1-1/2 in 1/4-20 Internal, 7000045286
3M 82975, Roloc D/F Cool Running Disc Pad TR, 3 in 1/4-20 Internal, 7010309116
3M 83980, Roloc Disc Pad TR, Extra Hard 4 in 5/8 -11 Internal, 7000119300
3M 14215, Roloc Disc Pad TS and TSM, Medium 3 in 1/4-20 Internal, 7000119310
3M 45179, Roloc Disc Pad TR, Medium 4 in 1/4-20 Internal, 7000045281
3M 45093, Roloc Disc Pad TR, Extra Hard 3 in 1/4-20 Internal, 7000045285
3M 45099, Roloc Disc Pad TR, Medium 1-1/2 in 1/4-20 Internal, 7000045280 