RollerFeedertm Aspects' patented RollerFeedertm offers backyard birders an exciting feeder that works on three levels. It is a terrific hopper feeder for small birds, it is squirrel proof and it is just plain fun to watch. This ingenious design truly frustrates hungry squirrels and saves valuable food for birds. The feeder is elegantly simple - a freely rotating outer shell surrounds an easy-to-fill hopper. The hopper is stationary, but when a squirrel climbs onto the outer shell, the squirrel's weight flips it harmlessly to the ground. The two-sided seed hopper stays upright inside while the exterior shell pivots around, keeping the seed intact. Rollerfeeder's weight-balancing feature allows the smaller and lighter songbirds like chickadees, nuthatches, finches and titmice the ability to feed uninterrupted in a safe, easy to maintain, covered feeder. Also, heavier birds will tilt the RollerFeeder just enough to prohibit them from feeding from the tray. This unique design is adjustable with weights provided. It features a rust-proof aluminum housing that has a forest green UV powder-coated finish. 2 qt capacity.