In tests, it failed to adhere to dusty or muddy tanks and if the user was not careful after freeing the grenade from its casing, it could easily stick to their uniform. The Ordnance Board of the War Department did not approve the grenade for use by the British Army, but intervention by the prime minister, Winston Churchill, led to the grenade going into production. Between 1940 and 1943, approximately 2.5 million were produced.