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 04258, Scotch Printable Flatback Paper Tape 256, White, 2 in x 60 yd, 6.7 mil,24/Case, 7000123288
Insize 6300, MICROMETER STAND, 6928640307294
3M 28385, Square/Cross Pad Mandrel 28385, 1/4 in 3-48 external, 7010362491 