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?).

Insize 4120-20, METRIC THREAD RING GAGE, GO, M20x2.5, 6928640341519
3M 26583, Accuspray Refill Pack for PPS Series 2.0, Green, 1.3 mm, 7100152953
3M 32201, HoldFast 70 Cylinder Spray Adhesive, Clear, Mini Cylinder (Net Wt 8.5 lb), 7100138480
Norton 66623325035 - 2" 120 Grit Fine Grade Aluminum Oxide Vortex Rapid Prep Green TR Non-Woven Surface Preparation Disc, 50 Each
3M 7494, 922, Disc Pad Holder 922, 2 in x 1/4 in Shank, 7000045864
3M 26130, PPS Series 2.0 Adapter, Type S35, 16 mm Female, 1.5 mm
Thread Stretched, 7100135926 