A Jackknife (Tools) is a knife with the blade pivoted to fold into a recess in the handle.
The jack knife was issued to nearly all soldiers in the Second World War. It was a useful tool many kept after their return to civilian life. There are several variations on the jack knife depending on period, service and manufacturer, including examples with spikes for opening out ropes.
The jack knife shown is around 70mm long, with a black plastic grip and a loop to which a lanyard may be fastened.
The lanyard (cord) was passed around the waist, through the belt loops, and the knife dropped through the loop at the end, allowing it to be stored in the trouser pocket with no danger of it getting lost. This knife is more compact than its 1WW counterpart, which was 5” long.
Once unfolded there is a (a) blade; and (b) combined tin opener and screwdriver. The knife has the manufacture name, date This Company produced clasp knives in the Second World War that were made in Sheffield England.
Description: This 2 WW vintage 3-piece Army/Jack Knife manufactured by H.M Slater was issued in 1949. The body of it measures 90mm, the blade measures 70mm, the tin/bottle opener measures 70mm and the shackle measures 70mm. The jack knife weighs 150g. A shackle is a “U” shaped connection with a “bolt” through the open end. (See photo at left where the lanyard attaches to the knife is called the shackle.)