The Mk XII was the first production version of the Spitfire to use the Rolls-Royce Griffon engine The Griffon was a development of the R sprint engine used in the Supermarine Schneider Trophy racing seaplanes of the late 1920s & early 1930s The low level performance of the Mk XII was very useful when dealing with low level hit & run raids mounted by the Fw 190 & later helped against the V-1 though the mark did not enter mass production Only 100 were built equipping two squadrons
- No 41 received its Mk XIIs in February 1943 & No 91 in April 1943