Dimart Fish Tank Aquarium Pump Duckbill Nozzle Free Rotate Flow Water Outlet Return Pipe Wide use at Aquarium, fish tank and pump. Use with circulating pump or return pipe. Good function: it can freely adjust the direction of flow Measurement: inner diameter: 1.4cm, outer diameter: 1.6cm, duckbill(LxW): 5x2.8cm Perfect water outlet for various types