The "Best1" feeder's  counter sunk cap is designed to prevent bees and other birds from drinking the nectar. The high impact styrene red bottom eliminates rust and discoloration because of the high quality materials. This 32 oz feeder will hold a lot of nectar to accommodate lots of hummers. Having only four parts, it is one of the easiest hummingbird feeders to clean. The "Best1" products are among the "best" in the market.