Keep large birds and squirrels out of your bird feed with a Yankee Dipper Bird Feeder! This feeder's weight-sensitive perches allow smaller song birds to feed while blocking all squirrels. The metal cap creates a barrier, stopping squirrels from lifting the tube to access the seeds. The 4-3/4" x 17" tube is made of durable, UV-stabilized polycarbonate that holds up to the weather. This squirrel proof bird feeder is the ideal feeder to use to keep your smaller backyard birds happy and the squirrels out.