We used this product under the mattress in our truck camper. We were shocked to discover mold on the underside of our mattress. We replaced the mattress and put the Hydravent down and it allowed air circulation and solved any further problems.
It is expensive, but we felt it was very worthwhile.
2014 Triple E Regency GT24MB (Murphy Bed) with all the good stuff
towing a 2016 Jeep Cherokee TrailHawk
Berkley, the amazing camping cat missed dearly (1996-2012)