Do you have the following troubles?
The toilet water flows back into the water pipe, causing the situation that the kitchen faucet bleeds blue water.
The hot water inside the electric water heater backflows, causing its dry burning or even explosion.
Solar hot water flows back to the water tower, resulting in wasted hot water energy.
You need a check valve to prevent water backflow. Only allow water flow in one direction.
Package: 1 pack
Type: male to female, female to male and male to male. Please pay attention to the flow of the liquid. Size: 1/2 inch
Warm Tips :The product is G thread, straight thread(Not NPT), please check your need before purchasing.