Therm-a-Rest RidgeRest SOLite Mattress Advanced Warmth:Patent-pendingThermaCapture surface boosts warmth by reflecting radiant heat back to your body. Light & Durable:Virtually indestructible and light enough to carry anywhere. Unique Design:Soft peaks andheat-trapping valleysprovide exceptional comfort. Reg: 20" x 72" / Large: 25" x 75" / Small: 20" x 48" R-Value: 2.8