Droll Yankees – Squirrel Proof – Yankee Whipper Bird Feeder. The Yankee Whipper Bird Feeder has four specially calibrated curved perches that allow birds of all sizes to feed, but collapse under the weight of a squirrel. Keep squirrels away from your bird feeder and save seed! The 5 pound capacity Droll Yankees Yankee Whipper Bird Feeder is a weight sensitive collapsing curved perch feeder that supports birds and not squirrels. It allows the birds to eat and saves seed by keeping squirrels away. The Whipper features four seed ports with individual weight sensitive perches. Curved perch design encourages cardinals and small songbirds to eat, but prevents squirrels from feeding. Each perch is individually sprung and calibrated to collapse when approximately 2 oz. or more rests on the perch. Length and girth of the feeder are specific to repelling squirrels. The heavy metal cap is constructed to prevent squirrels from raising the cap and reaching the seed inside. An internal baffle design delivers the seed to the ports. The 4-3/4″ x 17″ clear feeder tube is made of UV stabilized poly-carbonate for long lasting durability without yellowing. The metal cap and feeder base are powder coated a stunning Evening Blue. The Whipper hangs from a looped stainless steel wire that reduces motion that would spill seed. Add a Locking Chain to secure it against falls. Components made in the U.S A. and in China. Lifetime Warranty against squirrel damage.