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 26140, PPS Series 2.0 Adapter, Type S45, 1/4 Female, 19 Thread BSP, 7100135336
3M 26022, PPS Series 2.0 Adapter, Type S12, 10 mm Male, 1.0 mm Thread, 7100135943
3M 26120, PPS Series 2.0 Adapter, Type S28, 17.5 mm Female, 19 TPI
Thread, 7100135956
3M 07056, Drywall Sanding Sponge CP-042, Single Angle, 2-7/8 in x 4-7/8 in x 1 in, Fine, 7100101555 
