It was formed in 1986 from the merger of Petters Limited and R A Lister and Company. At that time the company was part of the Hawker Siddeley group, but today L-P is independent. Its products are in the smaller end of the diesel engine market, ranging from single-cylinder air-cooled engines of 2.7 horsepower (the 'Zeta' series) up to the 64 horsepower 'Delta' engine. One higher-horsepower engine of up to 335 horsepower, the 'Omega' is also produced. The engine designs range from modern high-speed turbodiesels (such as the 'Gamma' or 'Omega' engines) to traditional single-cylinder medium-speed types such as the 'A-Series' and 'Phi' types.