One way valve for shower drain

[kolega]

Can someone tell me what sort of one way valve I need to get for the shower drain to stop sink water returning and where would I purchase such a valve?

Thanks
David

 

[achjimmy]

Hi what van and where is the sink water coming up, the shower?

 

[Stone Stomper]

Hi David, I used one from Whitworths Marine and changed the twin manifoldJayco use to a single out let, the one way valve from here https://www.whitworths.com.au/main_itemdetail.asp?item=91855&search123=valve&intAbsolutePage=1

Christian

 

[Bushman]

Bunnings have one way valves in the PVC plumbing section, but mines never been an issue with the dual outlet (YET) though you quite often here the gurgling from the shower as the sink water rushes out