andy198712 wrote:who copied who though....
Well, the Krankvent is using a different patented design/materials and has been around in it's present form for awhile.
The others look similar on the OUTSIDE and make similar claims/price but use the slow valve setup that cannot WORK as well.
Looks like the "copies" aren't really "good" copies, they just try to charge the same $$, look and the ads "sound" the same for a cheap part.
As I said, AIR valves are pretty cheap.
The other folks (at best) are using a similar design, so you are likely paying $74 for the nice welded SS housing with a twenty cent valve in it.
The Krankvent probably costs about the same to the manufacturer to make, at least for the element.
If they were $25 I'd have several in use.
Decent plastic would be fine, if it came apart for cleaning I'd be impressed.