Allstar 0.675 inch O.D 11/32 inch Umbrella Style Engine Valve Seal (Pack of 16) for Stock Diameter Spring feature engine valve seals. They measure 11/32 inches and have an umbrella style for use with stock diameter valve springs. The o.d. of seals are .675 and require no machining for installation. They are sold as one set of 16 pieces and are backed by a 90-day limited factory warranty.