Jack Nut:
The threaded insert is a blind fastener designed for use in thin, soft, or brittle materials. When tightened, the body of the jack nut collapses to form legs which grip the inside of the mounting surface, leaving a permanent, reusable threaded insert.
Jack nuts are available in steel only, small packs of 10, 25 and 50, regular packs of 100, 500 or 1000
Jack nuts fasten in a blind hole, designed for plastics or thin sheet metals and fastens securely despite burrs or uneven substrate.
This fastener is only offered in steel with a zinc plate.