Foil fencing

A foil is one of the three weapons used in the sport of fencing, all of which are metal. It is flexible, rectangular in cross section, and weighs under a pound. As with the épée, points are only scored by contact with the tip, which in electrically scored tournaments is capped with a spring-loaded button to signal a touch. A foil fencer's uniform features the lamé, a vest, electrically wired to record hits in such cases. It is the most commonly used weapon in competition.

There are two common types of foils, the nonelectric foil—also known as "steam" or "dry"—and the electric. The components common to both varieties are the pommel, grip, guard, thumb pad, and blade. The blades of both varieties are capped with a plastic or rubber piece, with a button at the tip in electric blades, that provides information when the blade tip touches the opponent. (There are also a range of plastic swords made by varying manufacturers for use by juniors.) Lacking the button and associated electrical mechanism, a judge is required to determine the scoring and the victor in a tournaments with nonelectric foils.

Nonelectric ones are primarily used for practice. The Fédération Internationale d'Escrime and most national organizations require electric scoring apparatus since the 1956 Olympics, although some organizations still fence competitively with nonelectric swords.

Foil have standardized, tapered, quadrangular (rectangular) blades that are made of tempered and annealed, low-carbon steel—or maraging steel as required for international competitions—and are designed to bend upon striking an opponent in order to prevent both injuries and breakage of the blade. The foil blade is no more than 90 cm in length with a blunted (or foiled) tip, the maximum length of the assembled weapon is 110 cm, and the maximum weight is 500g; however, most competition foil are lighter, closer to 350g.

The blade itself is subdivided into 3 regions: the foible, or "weak", the last third of the blade near the tip; the medium; and the forte, or "strong", the third of the blade near the guard. Inside of the grip is the tang, which is threaded at the end to allow the pommel to fasten the foil assembly together. When an Italian grip is used, see below, a ricasso extends from under the guard, inside of the grip's quillons, into the tang.

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