The second evolution of the Aston Martin DB4 - Base Model was introduced in 1960. Known as the Series II, these updated sports cars were only offered in a coupe body style that featured a 240hp 3.7L inline six engine that sent drive to the rear wheels via a 4 speed manual transmission. Series II cars were the first DB4s to feature window frames for the passenger doors, as well as a few other improvements such as a front-openning hood. In addition to various small aesthetic changes, the Series II also featured enlarged oil capacity, as well as an optional oil cooler and improve front brakes. A total of 349 Aston Martin DB4 Series II cars were built before the introduction of the Aston Martin DB4 - Series III.