Our stainless steel tube nuts are the ideal solution for mounting your fuel, brake, and oil lines. Machined with precision these stainless steel tube nuts feature an ultra-smooth finish along their threads that ensures a tight, leak-free connection every time. 5/16" (1/2-20 I) Thread Size - Stainless Steel Construction - Universal Design - Ultra Smooth Finish Along Threads. - Highly Durable & Leak Proof: With stainless steel construction and ultra smooth finish along threads you can expect unbeatable durability and a leak proof connection every time you install one of these tubes nuts. - Easily Install onto Any Part - The universal design of our 5/16" (1/2-20 I) tube nut make it easy to thread into any part from fuel, brake or oil systems with ease.