All ADA Racing billet heads are made from 6061-T6 aluminum and CNC machined for consistency and performance. Clear anodized for looks and protection against corrosion. This is the head shell only. Includes orings that fit into the grooves in the head shell and brass fittings. This head uses the stock orings in the top of the cylinder. Please note that the water routing is not the same as stock. The head shell is one piece, but it does not allow water to pass from one cylinder to the other. Water is routed into the head pipe of the exhaust and exits out the head to the water bypass. Select domes under Related Products below.