Stainless Steel Phillips Oval Head Machine Screws 18-8 Stainless Steel Includes 303 & 304 Grades Right Hand Thread, UNC Fully Threaded For Use With A Pre Tapped Hole Or Matching Hex Nut. Rust and Corrosion Resistant Oval Head Machine Screws Have a Countersunk Head with a Raised Dome Top. Standards: ANSI B18.6.3