Development of a navalised Spiteful was pursued during 1945 to Specification N.5/45, and a contract was placed for two prototypes and 150 series aircraft, the name Seafang being assigned. A Spiteful F Mk 15 with a "sting"-type arrester hook was tested early in 1945, and the Seafang prototypes flew in the following year. One of these represented the production Seafang F Mk 31 with Griffon 61 engine and a long-stroke undercarriage, but non-folding wings. The othet represented the Seafang F Mk 32 with a Griffon 89 engine with contraprop, and upward-folding wings. Armament comprised four 20mm cannon and provision was made for carrying a pair of 454kg bombs or six 136kg rockets. After completion during 1946-47 of 10 Mk 31s and six Mk 32s (some of which were never flown) production was cancelled.