These high tech nitrous plates bolt between the upper and lower intake manifold on Holley Hi-Ram manifolds for a quick and clean install. Nitrous and fuel are injected into each cylinder from the side of the runner providing direct port like distribution without having a flow restricting nozzle or spray bar in the runner. The plate is made from billet aluminum with passages machined directly into the plate so there is no need to worry about spray bars breaking or spinning.