All Metal Champion Platform Bird Feeder lets you feed a variety of birds and deter squirrels. This metal platform bird feeder foils squirrels with its two Squirrel Blocker grids! Simply fill with a layer of black oil sunflower seed, so the bottom grid rests on top of the seed. The two grids fence out squirrel noses and squirrel paws and prevent them from reaching the seed. All metal every bit of this feeder is completely chew proof. Duncraft's 5 Year Guarantee.