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 51632 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 1/8" Collet
Insize TLP-300H-C2, BT50/BT40 converter, 6928640377259
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Dynabrade 53533 Cone or Plug Grinder (Triple Extension) 