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?).

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3M 81732, Disc Pad Face Plate Ribbed, Extra Hard, Red, 5 in, 7000120517
3M 53914, Performance Plus Duct Tape 8979N Nuclear Red, 48 mm x 54.8 m 12.1 mil, 7000049014, 24/ case
Dynabrade 53533 Cone or Plug Grinder (Triple Extension)
3M 30702, Cloth Belt 577F, 50 YF-weight, 2 in x 132 in, Film-lok, Single-flex, 7010363104, 50 per case
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3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093 
