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
3M 30694, Cloth Belt 577F, 60 YF-weight, 1/4 in x 24 in, Fabri-lok, Single-flex, 7010308882, 200 per case
3M 29824, Sanding Screen, 80 Grit, 20 in x NH, 7100160247
3M 77257 Scotch-Brite Durable Flex Belt, 3/8 in x 13 in, A CRS, 10 per inner, 7010409609 