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 43267, Speedglas Welding Helmet 9100FX 06-0600-30iSW, with 9100XXi ADF Shades 5, 8-13, 1 EA/Case, 7100259848
Standard Abrasives 32953, PSA A/O Disc, 711880, 2 in x NH, 60, 7010310798
3M 92250, Extra Large Single Angle Sanding Sponge 910PSA-12-CC, 2-7/8 in x 8 in x 1 in Fine, 7100101547 