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 Flatback Tape 2517, Medium Brown, 36 mm x 55 m, 6.5 mil, 24Rolls/Case, 7000088501
Dynabrade 95677 1/4" Male Plug with 1/4" NPT Female Thread
3M 07056, Drywall Sanding Sponge CP-042, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101555 