uxcell 12 Piece Plastic Fish Bowl Aquarium Air Pump Check Valves, Red/Clear Product Name : Aquarium Check Valve; Use for : Fish Tank, Aquarium Hole Inner Diameter : 2mm0.08"; Total Size : 5.3 x 1.5cm/2.1" x 0.6"(L*Maximum Diameter) Material : Plastic; Color : Clear, Red Weight : 45g Package Content : 12 Pcs x Aquarium Check Valve