Stores reference 6A/1202. .303 Ammunition Counter, MK.1A. 1942 dated. Intended to allow the pilot/airgunner to see the level of remaining ammunition. He would set the number of rounds available for the gun before take-off using the central metal knob. Approximately 6cm diameter with black dial and luminous numbers reading from zero to 1000 'rounds'. Excellent unused condition with box of issue (worn). Rare. Stock code M21018.