McAlpine 40mm Anti-Syphon Adjustable Inlet Bottle Trap with Multifit Outlet C10AV

If you are fitting a sink or bath upstairs and don't fancy gurgling noises every time downstairs uses a sink eff then you need a bottle trap with a Pressure valve. It will stop that gurgling in one step. So that's it, it works.

Easy to fit, gave 3 stars as not 100% certain it has reduced backflow as much as anticipated

As you would expect from mcalpine a top quality part that does what it says.

This trap looks fine until you use it; I think there is a mismatch on the threads - it's only microns - but it's enough to cause joints to weep. Need to keep a roll of PTFE tape handy and DON'T put the sides back on the bath etc, until you have let it run for a few days to check for leaks !!!!!!!

the adjustment and reliability

missing part

Does the job, no more gurgles!

Does what you'd expect for McAlpine. No issues with it whatsoever.