The plant hangers are made from stainless steel and aluminum strapping. These were used for securing shipping crates for overseas shipment. They were used because they are not affected by salt water and spray. We pick these up in the Chicago land area and upcycle them into the plant hangers. They are made to accept a standard 4" diameter or smaller pot. The plant hangers allow the homeowner to blend their rain barrel into the yard with a more ascetically pleasing look.