This is a 100% Stainless Steel Open Style Trailer Lug Nut. This Lug Nut has common 1/2-20 Thread, that installs with a 13/16 socket or lug wrench. This Trailer Lug nut will fit most 4 lug, 5 lug, 6 lug, and 8 lug trailer hubs and brake drums. Because this product is 100% Stainless Steel, it will not Rust!