The de Havilland Mosquito NF Mk II was a two-seat twin-engined day and night long-range fighter and intruder. Although initially envisaged as a day fighter, the F Mk II, it was used as a night fighter. It was powered by two Merlin 21 or 23 engines in long nacelles, and armed with four 20-mm cannon in the lower front fuselage plus four 0.303-in (7.7-mm) Brownings in the nose.
As a night fighter, it was equipped with AI Mk IV or Mk V radar (with arrow-head aerials), and initially pained in overall non-reflective black. However, this night finish caused the maximum airspeed to be reduced by 25 mph. As a result, camouflage was changed to a smooth black, but this caused too much reflection, so was agin changed to dark green and medium sea grey.
A total 589 Mosquito NK Mk. II fighters were built (including 199 converted to NF Mk XII & XVII with upgraded radars). Initial deliveries to No 157 Sqn, started in March 1942.
Twenty-five NF Mk. IIs were modified for intruder operations and employed by No. 23 Sqn, without AI but with extra fuel.