Plastic One Way Air Pump Control Check Valve for Aquarium 12mm 5 Pcs Product Name : Aquarium Air Pump;Type : One-Way Material : Plastic;Color : White Connector Dia. : 9 x 12mm/0.35" x 0.47"(Inner Dia*OD);Total Size : 3.9x 2.2cm / 1.5" x 0.87" (L*W) Weight : 17g Package Content : 5 x Aquarium Air Pump