These have a go gauge on one end and a no-go gauge on the other end.

Check a part’s external threads to make sure they fall within tolerance. You can use these for bolts, threaded rods, bits, and more.

Inspect fasteners and verify threads with this checker.

Find thread size, screw size, diameter, and drill bit size with one tool.

Mount to a wall for easy access, and thread your fastener into holes or onto plugs for quick and accurate size identification.

Determine threads per inch and thread pitch on nuts, bolts, and other fasteners.