All Squirrel Buster® Seed and Peanut Feeders work in the same way – when a squirrel lands on the bird feeder its weight automatically closes the feeding ports, denying access to the bird food inside and not harming the squirrel in any way. These high-performance feeders are 100% effective when hung with at least 47cm clearance all around, forcing the squirrel to climb on to the bird feeder and trigger the closing mechanism. They have also been designed to dismantle easily for filling and cleaning.