Snap traps are devices consisting of a wooden base and a metal mechanism designed to kill rodents that approach. The animal, attracted by the bait placed on the trap, lowers the plate with its weight, triggering the percussion bow connected to it and held under tension by a spring. When activated, the bow hits the rodent in the head or neck, causing its death. However, in practice, it is not uncommon for animals to not be fatally struck and may suffer for some time. This can happen if the trap is not sized for the species for which it is designed, if the impact force is not sufficient, or if the animals do not enter the trap as intended. There is also another type of snap trap that works differently, which has circular openings inside a wooden block with strings inserted into the holes. Inside these openings, a bait is placed attached to a stick under tension. When the bait is moved by the rodent, the stick snaps, lifting the strings and causing the rodent to be killed.