The Victor Professional Rat Trap isspecifically designed for professional pest management use. Victor Pro RatTraps are equipped with a unique setting control which allows you to use a softor sensitive setting for normal situations or a firmer setting in situationswhere vibrating machinery or other manufacturing operations could prematurelyset off the trap. Can be used baited or unbaited. A typical unbaited trap isplaced perpendicular to a wall's surface where the rats are travelling, forcingthem to pass over the triggering plate and will be captured.