Uxcell 2-Piece Plastic Fish Tank Aquarium One Way Air Flow Control Valves, Clear/Red Aquarium Air Pump; Type : One-Way Material : Plastic; Color : White, Red Connector Inside Dia. : 4mm/0.2";Total Size : 5.3 x 1.5cm/2.1" x 0.6" (LxW) Weight : 7g Package Content : 2 x Aquarium Air Pump