This ultra-durable poultry waterer mounts in small spaces, making it a great choice for those cute tiny coops for a few backyard hens. Holds 2 gallons of water. Made of potable-grade PVC plastic and mounting brackets are included. To fill, remove the top lid and fill unit with water, replace the top. Ensure that the lower float cup fills properly. Chickens drink by moving small float valve in the red cup with their beak. Matches item HEFD High End Hen Poultry Feed Saver.