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 97566 1/4" Safety Coupler, Female
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3M 54765, SandBlaster Right Angle Grinder Multi-Layer Disc 9679 60G 4-1/2 inch, 7010339877
3M 26120, PPS Series 2.0 Adapter, Type S28, 17.5 mm Female, 19 TPI
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3M Super Abrasives Roloc Disc, 2" Type-R, Medium AO High Strength, Box of 50
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