Keeps unwanted varmints like squirrels and bird from digging around feeder unit trying to get feed. Reduces wasted feed. Delivers a non-lethal shock to deter varmints. Mounts inside any R-Kit series feeder. Make sure the feed you are putting in your game feeder is going to the game you want to feed with the American Hunter R-Kit Varmint Buster Zapper. This devices give unwanted visitors, like squirrels and birds, a non-lethal shock to deter them from the feeder. Unit mounts inside any R-Kit series feeder, including the R-Kit Pro and RD-Kit Pro, and connects to feeder battery.