I had Thermarest’s first Lightweight mattress, a rectangular 72″ mattress with diamond shaped holes in the interior foam. It lasted, amazingly, a few decades with a few patches but finally delaminated where I rested my head/face. Since I’m a stomach sleeper I figured my body oils and DEET repellant on my face had gradually penetrated the outer cover and defeated the laminate glue.
When I called Cascade Designs they said to send in the old mattress and they would send me in the current equivalent, a Prolite Regular. I did and they did, to my surprise. But then I remembered they also had replaced a 1980 3/4 length pad in 1989 whose brass valve had failed. Yes, the original Thermarests had brass valves. I am that old. I first use that original mattress while building the 9 mile Snow Creek section of the PCT just north of Palm Springs, CA. (And yes, children, I was a professional trail builder carving out the original PCT from wilderness.)
The “moral” to this story is to extend your inflatable mattress’ life by slipping a T shirt over the top of your mattress where you rest your face. It’s not only more comfortable but it saves the mattress.
