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 86804, Cubitron II Stikit Film Disc 775L, 80+, 6 in x NH, Linered w/Tab, Die 600Z, 7100045866, 250 per case
Dynabrade 77773 5" Dia. x 7/8" Center Hole, 60 Grit, Type 27, Ceramic DynaCut Flap Disc, 10/pack
Insize 7332, SPINDLE LIFT KNOB, 6928640312649
Dynabrade 94993 1/4" Male Composite-Style Coupler with 1/4" Female Plug Assembly 