Proflow's valve cover baffle kits are perfect for installing a breather system on your valve covers. They're designed for use on valve covers that do not have breather holes—or when an extra one is needed in a different location. The kits feature either a 1 in. double O-ring I.D. for use with most push-in breathers, or a -12 AN male thread for use with EVAC systems. They are baffled to prevent unwanted oil from pushing out of the breather. The baffles require an appropriately sized hole drilled into the cover; and include a lock nut, sealing washer, O-ring, and threaded baffle. Some models also include a breather.