Ferrea came out with Hollow Stem Lightweight Valves years ago revolutionizing the stainless steel valve market with a 22% lighter than your conventional stainless steel alloy valve. Made from exclusive Super Alloy materials, which they resist heat much better then conventional Inconel materials. Ferrea Hollow Stem Lightweight Valves are available in 7mm, 5/16, 11/32 and 3/8 stem diameters as well as semi finished blanks that we can machine for you application. Get the best in Valve technology today for your Race Engine!!!