Now there’s a choice of four great ways to keep squirrels locked out of a free meal. Squirrel Buster™ uses patented, proven technology to stop squirrels in their tracks while allowing visiting birds to feed freely. The moment a hungry squirrel climbs on board Squirrel Buster™, the feeder automatically shuts the ports to prevent access. It’s ingenious, it’s humane, and it really works.