One way
 
Durable
Efficient, Effective protection for your pump
Great one way check valve for aquarium air pump.
Non Return anti syphon valves to protect your electrical equipment. (air pumps etc)
Colour: red
Material: Plastic
Length: about 5.50cm/2.17"
Quantity:1Set(10pcs)

Package includes:
1Set(10pcs) x One Way Check Valves(not included others)