NO MACHINE OR REELS REQUIRED! Plug this buzzer into the 2-prong foil socket of your electric foil (any brand or size) and you’re off fencing “electrically”! Will indicate a buzzing sound for about 2 seconds every time the tip of your Foil is pressed (including the opponent’s guard). Thick metal casing will NOT break or dent easily. Measures about 1.75” wide by 1.5” long by 5/8” thick and weighing only a few ounces, it has a replaceable 12V (model 23A) internal battery. The unit has a small indicator light, too (goes off at the same time as the buzzing sound). Perfect for beginners, clubs, home-based fencers, etc. Does NOT distinguish between valid (lame) or off-target touches (including opponent's guard).