The patented squirrel Buster technology is truly squirrel proof. Thousands of delighted bird lovers have confirmed it. Guaranteed squirrel Proof Effective against Red and Gray squirrels Dismantles for easy cleaning By hand without the need to use any tools. 24 Month Factory Warranty How it works Openings in the wire shroud align with seed ports and provide birds access to the seed. When a squirrel climbs onto the feeder, its weight automatically forces the shroud down, closing access to the seed ports. All squirrels and many large birds are foiled but not harmed in any way.