For decades people have relied on the original Ridge Rest mattress to provide the lightest comfort possible, or to boost the warmth & durability of a three-dseason mattress for winter use. Now, with the Thermarest patent-pending, aluminized Solar coating, the Ridge Rest SOLite offers a 10% boost in warmth with even more durability from surface wear & tear. All of this with no appreciable weight gain makes it perfect for everything from extreme, high-altitude climbing to entry-level backpacking. Features Advanced Warmth: Aluminized surface boosts warmth, reflecting heat back to your body. Light & Durable: Virtually indestructible & light enough to carry anywhere. Unique Design: Soft peaks & heat-trapping valleys provide exceptional comfort.