fucked if I can use one myself but I’ve seen one used by an ex-army guy. Same idea as what’s on a swiss army knife I think….
Several can openers with a simple and robust design have been specifically developed for military use. The P-38 and P-51 are small can openers with a cutter hinged to the main body. They were also known as a “John Wayne” because the actor was shown in a training film opening a can of K-rations. The P-38 can opener is keychain-sized, about 1.5 inches (38 mm) long, and consists of a short metal blade that serves as a handle (and can also be used as a screwdriver), with a small, hinged metal tooth that folds out to pierce the can lid. A notch just under the hinge point keeps the opener hooked around the rim of the can as the device is “walked” around the rim to cut the lid out. A larger version, called P-51, is somewhat easier to operate. P-38 was developed in 1942 and was issued in the canned field rations of the United States Armed Forces from World War II to the 1980s. The P-38 and P-51 are cheaper to manufacture and are smaller and lighter to carry than most other can openers. The device can be easily attached to a keyring or dog tag chain using the small punched hole.
Official military designations for the P-38 include “US Army pocket can opener” and “Opener, can, hand, folding, type I”. As with some other military terms (e.g., jeep), the origin of the term is not known with certainty. The P-38 and P-51 openers share a designation with the P-38 and P-51 fighter planes, however this is coincidental. The most likely origin of the name is much more pedestrian; the P-38 is 38 mm (1.5 in) long. This explanation also holds for the P-51, which measures 51 mm (2.0 in) in length.
P-38s are no longer used for individual rations by the United States Armed Forces, as canned C-rations were replaced by soft-pack MREs in the 1980s. They are, however, included with United States military “Tray Rations” (canned bulk meals). They are also still seen in disaster recovery efforts and have been handed out alongside canned food by rescue organizations, both in America and abroad in Afghanistan. The original US-contract P-38 can openers were manufactured by J. W. Speaker Corp. (stamped “US Speaker”) and by Washburn Corp. (marked “US Androck”), they were later made by Mallin Hardware (now defunct) of Shelby, Ohio and were variously stamped “US Mallin Shelby O.” or “U.S. Shelby Co.
I can hand on heart say I’ve never tried the deep fried Mars Bar! Tried deep fried pizza once, it was bloody awful!! I’ll swing past the place that invented it one day and take a pic of the menu for you DB, some things on there WILL make you puke!