Alongside its new battledress uniform, the British Army reintroduced the Field Service cap in 1937. The design dated back to the start of the century and had been used, amongst others, by the Royal Flying Corps during World War I. It had fallen from favour and was largely replaced by regimental pattern caps or the stiff peaked service dress cap. The FS cap, however, was easy to fold flat and tuck into a pocket or pack and so was far more practical than the SD cap.