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The Rivnut,® or Rivet Nut, is a round or hexagonal body, internally threaded blind fastener. The Rivnut® provides a blind installation into sheet metal, plastic and tubular materials. It performs as a rivet to bind two or more materials together and as a nut for attaching a mating part with a screw into its internal threads.
The Rivnut® was originally invented by BF Goodrich in 1936 to install a rubber wing de-icer to the leading edge of an aircraft wing. The Rivnut® riveted the wing skin to an inner spar. A mating screw was then used to attach the rubber de-icing fixture to the wing.