These Aeroflow billet valve covers are machined from a solid block of 6061-T6 aluminium and then hand polished for an amazing finish. They feature super flat gasket rails that ensure no leaks and offer a superior seal for supreme vacuum retention. These covers fit LS1 or LS3 OEM style coils.Included in the covers is a female -6 ORB for custom plumbing options. Make a statement at your next car show with these awesome covers!