The Mercedes-Benz 300 was introduced in 1951. Also known as the Type 300, the 300 was a luxury four door car that represented one of Mercedes' most advanced and refined cars of the era. The 300 was built over two chassis, the W186 and the W189. The W186 was the first 300 offered, with three main variants over the course of its production. In 1957, the W189 was introduced, this 300 was known as the 300d and was offered on a lengthened platform. The Mercedes-Benz 300 is commonly referred to as the Adenauer, after the German chancellor Konrad Adenauer, who used the cars extensively during his tenure.