The Booby Trap is issued to the NVA Engineer kit. It appears to be a pair of wirecutters, but when used on a vehicle, the player will stick some TNT on it. This TNT trap will trigger immediately when a player enters the booby trapped vehicle, blowing it up and instantly killing the player.
A useful tactic when using the Booby Trap is to head for an enemy base, preferably a main base, and set traps on important resources, like helicopter gunships and tanks. For greater chances of success, the explosive should be placed in a spot easily overlooked, like the exhausts or wheels.
It is important to note that a booby trap will also trigger if a friendly soldier enters the booby trapped vehicle, resulting in a teamkill, even if the server has turned off friendly fire.