The aerospace standards for the round body, open end, Rivnut,® or Rivet Nut, are NAS1329, (Flat Head) and NAS1330, (Countersunk Head). The Rivnut® is around body, internally threaded, blind fastener. The Rivnut® was invented in 1936 to attach a rubber de-icer extrusion to the wing of an aircraft. It performs as a rivet to fasten two or more materials together. It performs as a nut for the attachment of a mating part with a screw.
The Rivnut® is offered in a Flat Head version or a Countersunk Head version which installs flush with the surface of the mating material. They are available in aluminum, steel, stainless steel, non-magnetic stainless steel, CH-alloy steel, and brass. Unified thread sizes of 4-40, 6-32, 8-32, 10-32, 10-24,1/4-20, 1/4-28, 5/16-18, 5/16-24, 3/8-16, 3/8-24,1/2-13 and 1/2-20 are offered. The Rivnut® installs in a wide variety of grip range, tolerances from 0.010 to 0.526 inches and from 0.25 to 10.50 millimeters. The military specification for the Rivnut® is MS27130,.
Rivnut® is a Bollhoff Rivnut® brand name. Liberty Engineering is an authorized Bollhoff Rivnut® distributor.