The Liberty L-12 is an American water-cooled 45° V-12 aircraft engine displacing 1,649 cubic inches (27 L) and making 400 hp (300 kW) designed for a high power-to-weight ratio and ease of mass production. It saw wide use in aero applications, and, once marinized, in marine use both in racing and runabout boats.

Hall-Scott Motor Car Company was an American manufacturing company based in Berkeley, California. It was among the most significant builders of water-cooled aircraft engines before World War I.