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 83539, Scotch Heavy Duty Packaging Tape Dispenser ST-181, Foam Handle with Retractable Blade, 7100288393
Dynabrade 77758 4-1/2" Dia. x 7/8" Center Hole, 60 Grit, Z/A, Type 27, DynaCut Flap Disc W/Fiberglass, 10/pack
Dynabrade 94991 1/4" Female Composite-Style Coupler with 1/4" Female Plug Assembly
3M 26140, PPS Series 2.0 Adapter, Type S45, 1/4 Female, 19 Thread BSP, 7100135336
3M 55630, Cubitron II Flap Disc 967A, 60+, T29, 7 in x 7/8 in, 7000148191
Dynabrade 53533 Cone or Plug Grinder (Triple Extension)
3M 15041, Scotch Electrical Shielding Tape 24, 1 in x 15 ft (25 mm x 4,6 m), 7000031348 