they are a really great tool!!!!, I have 4. they made several versions . 1. ww2 model no. 280, or 480,[off the top of my head for m. no.'s], 2. two or three commercial ones, one like the military, one with a long wood handle,w/ no knuckle guard. 3. there is also a vietnam era one made by frank and merril, stamped as follows, axe, survival tool. only difference between this one and a w.p. is it is about 1in. shorter to fit in pilots survival kit. they currently make at least 3 models that I know of. if you want there web add. or any other info, shoot me a p.m.