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 26128, PPS Series 2.0 Adapter, Type S33, 1/8 Female, 27 Thread NPT, 7100135950
Insize 4121-5C1N, AMERICAN STANDARD THREAD RING GAGE, NO GO, 5/8-11UNC, 6928640359408
3M 01326, PSA Cloth Disc 348D, P240 X-weight, 3 in x NH, Die 300V, 7000045069
Dynabrade 11476 Dynabelter Abrasive Belt Tool, Heavy-Duty
3M 26130, PPS Series 2.0 Adapter, Type S35, 16 mm Female, 1.5 mm
Thread Stretched, 7100135926
3M 26018, PPS Series 2.0 Adapter, Type S11, 3/8 Male, 18 Thread NPS, 7100135942
Dynabrade 14010 Dynafile Abrasive Belt Tool Versatility Kit
3M 26109, PPS Series 2.0 Adapter, Type S23, 1/4 Female, 18 Thread NPS, 7100135941
Norton 66261199696 - 3" X 1/4" X 1/4" Vortex Rapid Blend Unified Wheel, 7AM U2305, 40 Each
3M 01708, Scotch-Brite SST Deburring Wheel, ST-WL, 8S Fine, 8 in x 2 in x 3 in, 7000144590
3M 37024, Extra Large Drywall Sanding Sponge 910-DDA, Dual Angle, 2-1/2 in x 8 in x 1 in, Fine, 7010375249 