The product is, as my title suggests, completely waterproof. My 3-year-old son has been tested and that is always soaking wet ... this time it remained dry under the mattress protector! I have therefore been washed (without fabric softener !!!) and even dried at lowest heat in the dryer, everything was great, not run and still sealed! You sweat not, as the Polyurethane film luftdurchlässigist. It also rustles not unpleasant. The schooner is quite thin, but does the job! I would definitely recommend! Thanks!
