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 26432, PPS Series 2.0 Sealing Plug, 96 plugs per pack, 7100135627
Insize 6301, MICROMETER STAND, 6928640307300
3M 9450, Disc Pad Holder 917, 7 in x 5/16 in x 3/8 in 5/8-11 Internal, 7000028549 