Anti-Siphon S Trap

Has anyone seen this beast in the *real world* situation. Does it work as advertised ?

Plumb Pak has a S trap that they make that I am looking it - it's called a *anti siphon S trap*. On the pic, it looks like a hybrid trap - S trap with a bottle trap on the bottom part of the S portion.

I was planning to stub out with DWV differently with a AAV but will this S trap do the trick as well.


See old post for pics -
https://terrylove.com/forums/showthread.php?t=7252

Nevermind. Pricing on that thingamajigee was a whopping $105 !

I'm stick with plan B.

trap

I don't see any picture, but if it is a bottle trap, then they were produced way back in the 40's. The idea was that it would hold excess water so when the"S" trap siphoned, enough would stay in the "bottle" to restore most of the seal.