12-piece rocker-box cover gasket set for the following cars with 318 CID Polysphere (scalloped valve cover) engines: 1960-67 Plymouth Belvedere - Fury - Satellite - Savoy; 1960-62 Dodge Dart; 1960-67 Dodge Charger - Coronet - Monaco - Polara - 330 - 440. These polysphere engines have mechanical (solid) valve lifters that need to be adjusted periodically and you'll need a set of these gaskets every time that is done. Includes seals for the retaining screws