This high quality wild bird squirrel proof seed feeder has a simple effective mechanism that uses gravity to protect your bird seed from the squirrels it works in a 3 step process the squirrel approaches from above the squirrel attempts to climb on to the feeding section the squirrels body weight lowers the protective sleeve saving seeds for the birds r r the high strength and quality construction in stainless steel and aluminum means your feeder is virtually indestructible by squirrels