Throughout most of the Second World War, the standard anti louse powder issued to soldiers was called Al-63. Work had begun on developing the powder in 1939 with the aim of issuing it to men to treat themselves and their clothing for lice in the field. It was also hoped that it would act as a prophylactic and if applied to uniforms prevent lice from taking up residence in the first place. The original formulation used napthalene, cresylic acid, pyrethrum and derris root. After the supplies of derris root became unavailable when the sources were captured by the Japanese, a new formulation called AL63 MK II was developed which replaced this with South American cube root until DDT was issued to replace AL63 completely from 1944 onwards.
Between 1940 and 1944 AL63 and AL63 Mk II was the sole British Army louse powder and amongst other things was used to treat a typhus outbreak in Naples between 1943 and 1944. The AL63 was issued in a number of different packages, but the most common was a cylindrical tin that was issued to individual soldiers:
This is a Mk III formulation and I am unsure when this was introduced, however I have found a picture of a full box of these tins, marked up for the Royal Army Service Corps and dated 1945:
The tins themselves show no sign of military ownership, but this picture certainly shows they were what was used by the British Army.
The tin is red, with a large black band on the front with the brand name and indicating that it is for human use:
The rear of the can has instructions for use:
Interstingly the cap on the tin has a depression stamped into it across the top:
My suspicion is that this is to allow you to use a coin for extra leverage should the lid become stuck to the can.
AL63 was held by units as G1098 stores, a G1098 list for an Airborne Military Police Section c.1943 lists 16 tins…one per man in the section. I have been told that tins were routinely issued to men in Italy to carry in their packs as lice was so prevelant in that theatre.