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?).

Dynabrade 92296 - 4" (102 mm) Dia. RED-TRED Eraser Disc Assembly
Insize UTM-E100, DIGITAL UNIVERSAL TESTING MACHINE, 100kN, 6940561908565
3M 16091, PPS Mix Ratio Inserts, Large (28 fl oz), 7000028411
Dynabrade 92153 1/2" W x 12" L 80 Grit Ceramic DynaCut Scalloped Edge Belt, 50/pack 