In the spring of 1943 the Hurricane Mk.IV entered RAF-service. Externally the aircraft was almost identical to the standard Mk.II, the extra armoured radiator's angular shape being readily identifiable. The main new feature on the Mk.IV however was the universal wing, incorporating a fixed gun armament of two Browning 0.303in (7.7mm) and was further capable of mounting two 40mm Vickers 'S' anti-tank guns in underwing blisters or one 250 lb (113.4 kg) or one 500 lb (226.8 kg) bomb under each wing. Alternatively on these hardpoints a long range fuel tank of 45 gallons (200 litres) or 90 gallons (400 litres) could be carried.
The universal wing was also wired to carry Rocket Projectiles as well as a Smoke Curtain Installation (SCI) to lay smoke screens.


In total 524 Mk.IV Hurricanes were produced by Hawker and Austin Motors. Although the first test flights of the Mk.IV 'prototype', KX405, were performed with a Merlin 32 driving a four-bladed Rotol propeller, production aircraft were fitted with a Merlin 24 or 27 with a three-blade propeller.