Here at SKPParts.com, not only do we listen to the Tractor pullers and their demands, we also take pride in offering several products to the Diesel Truck Enthusiast! One if which is our line of Delivery Valves. We ask that all customers take up on the offer to turn in there cores. This helps us keep our pricing Way below other competitors! All purchases inlude Delivery Valves and Holders! Don't let the power delay, CALL TODAY!!!