These Polished Hamburger's fabricated aluminum valve covers are for use on BB MOPAR (383-440) engines. They are super strong, yet very lightweight. They are precision manufactured using 1/4" rails to provide a positive seal and eliminate oil leakage between the valve cover and head. This pair of valve covers has no breather holes, allowing you to locate them as your situation requires. They measure 3-3/4" tall and have a great looking Polished aluminum finish that is easy to maintain. This set includes mounting hardware, but gaskets are sold separately.