Don't let the orange paint fool you. These are fresh-out-of-the-box aluminum Pro Action 24-degree cylinder heads from RHS. They came complete with hardened seats and bronze valve guides. The intake valves are 2.250 inches, and exhaust valves come in at 1.880 inches (11/32-inch diameter for both). They also come with dual 1.509-inch valvesprings, 3/8-inch guideplates, and 7/16-inch rocker arm studs.