uxcell Fish Tank Aquarium Red Clear Plastic Air Pump Check Valves 5 Pcs Product Name : Check Valve;Use for : Fish Tank, Aquarium Air Hole Diameter : 3mm/ 0.12";Overall Size : 5.3 x 1.5cm/ 2.1" x 0.58"(L*Max.D) Material : Plastic;Color : Clear, Red Net Weight : 19g Package Content : 5 Pcs x Aquarium Check Valve