The Tomcat Mouse Killer III Refillable Bait Station is a kid-resistant refillable bait station and includes eight 1-ounce bromethalin block baits. One block can kill up to 12 mice and this package contains enough bait to kill up to 96 mice. Mice enter the station, eat, leave and die. The Tomcat Mouse Killer III Refillable Bait Station contains the active ingredient bromethalin, which kills in 1 to 2 days (versus 6-10 days for first-generation anticoagulants)