ITEM NAME:3 Pcs Non-return Plastic Air Pump Check Valves Clear for Aquarium J6F1 3 Pcs Non-return Plastic Air Pump Check Valves Clear for Aquarium J6F1 Product Name: Check Valve Use for: Fish Tank, Aquarium Hole Diameter: 1.7mm/ 0.06" Total Size: 5.3 x 1.4cm/ 2.08" x 0.55"(L*Max.D) Material: Plastic * Protect you air pump by preventing aquarium water from back siphoning during a power outage. * Place in your airline tubing between your air pump and aquarium water to prevent water returning down the air line. * Color: Clear * Weight: 12g * Package Content: 3 Pcs x Aquarium Check Valve Note:Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm..Use for: Fish Tank, Aquarium. Note:Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. Color: Clear.