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 77769 5" Dia. x 7/8" Center Holes, 80 Grit, Z/A, Type 27, DynaCut Flap Disc w/Fiberglass, 10/pack
Air Turbine Tools 2545SVF - 1/4" Angle Hand Tool Series (Long Version, Front Exhaust), 30,000RPM, 35532
Insize 3101-225E, DIGITAL OUTSIDE MICROMETER, IP65, 8-9"/200-225mm, 6928640326868
3M 26102, PPS Series 2.0 Adapter, Type S16, 3/8 Female, 19 Thread BSP, 7100135934
3M 26130, PPS Series 2.0 Adapter, Type S35, 16 mm Female, 1.5 mm
Thread Stretched, 7100135926
3M 26116, PPS Series 2.0 Adapter, Type S25, 1/4 Female, 19 Thread BSP, 7100135957
3M 03126, General Purpose Sanding Sponge CP040-6P, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101532, 6/pack 