Centurion’s Hummingbird Feeder is made of durable, high-quality plastic and comes fully assembled and ready to hang. The clear glass Feeder holds 30 ounces of nectar which can be easily monitored to see the nectar level for refilling. The Flower-shaped feeding ports and perches allow several birds to feed simultaneously. The mouth of the reservoir tightly screws onto the base, effectively sealing the bird feeder, no tools are required. After filling the container and screwing it onto the base, just flip it upright; the feeder will not leak even while upside down.