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 97571 1/2" NPT Male Safety Coupler
Standard Abrasives 727338, Zirconia Straight Cartridge Roll, 1/4 in x 1-1/2 in x 1/8 in 60, 7100102754
Dynabrade 98272 1/2" NPT Female Plug
3M 15041, Scotch Electrical Shielding Tape 24, 1 in x 15 ft (25 mm x 4,6 m), 7000031348
Dynabrade 77757 4-1/2" Dia. x 7/8" Center Hole, 40 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
Insize 6140, DEPTH BASE ATTACHMENT, suitable for calipers with beam width (w) .630", 6928640303579
3M 07053, General Purpose Sanding Sponge CP-040NA, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100110752 