This unique accessory allows for the installation of a permanent threaded insert for thread repairs or for a completely new retention device. Easily removable for periodic maintenance while providing a firm base that resists stripping of the threads and pulling through the mounting surface as is common with sheet metal screws. Available in a variety of thread sizes (6-32, 8-32, 10-24, 10-32, 1/4''-20, 5/16''-18 and 3/8''-16) in a 76 piece kit with an installation tool, mandrels and rivet nut inserts. Simply drill a hole in the frame rail or panel, insert the threaded rivet nut using the handy tool and add a bolt & washer (not included).Rivet Nut Replacement Parts, Material Thickness & Drill Size Chart