Repair your pond with the Pondmaster 12575 MD/PM 3-5 Replacement Impellers. This strong and durable impeller is finished with a black coating that inhibits algae growth. This unit is easy to install and provides reliable performance in your water garden. Dimensions: 4W x 1.5D x 6H in.. Made from plastic. Black finish. Replacement impeller for water gardens. Magnetic drive.