For the 1959 model year, the small British car company Bristol replaced the 404 and 405 models with the 406. The 406 would be the last of the straight six BMW-based engine vehicles. It was a continued step forward for Bristol. The car featured four-wheel disc brakes, a larger displacement engine, and an overdrive that would shut off on its own. Two 406s were bodied by Zagato and had a strikingly different exterior design. The 406 was only offered in a two-door coupe. One hundred seventy-four total examples of the 406 were made until the car was replaced in 1961 by the 407.