This item is for a set of 8 stainless steel exhaust valves and 8 intake valves and hardened LOCKS for SB Chevy engines. The exhaust have 1.500" head diameter, 4.905" stock length, and .3415" (11/32") stock diameter stems. The intake have 1.940" head diameter, 4.905" stock length, and .3415" (11/32") stock diameter stems. They are made by Elgin Industries and are brand new. They will fit many small block Chevy 283 302 305 307 327 350 383, and 400 V8 engines and also could fit many aftermarket heads from Dart, Edelbrock, Pro Topline, and World Products depending on the head diameter size and length you need for your application. Intake: Head Diameter: 1.940" Swirl polished head with undercut stem. Valve Length: 4.910" Tip length: 0.250" Stem Diameter: 0.3415" (11/32") Stem Type: Chrome plated fully machined stem with undercut -1 Groove. Exhaust: Head Diameter: 1.500" Swirl polished head with undercut stem. Valve Length: 4.910" Tip length: 0.250" Stem Diameter: 0.3415" (11/32") Stem Type: Chrome plated fully machined stem with undercut -1 Groove.