Made from cold yarn, a man-made fabric, the CoolTEC Fabric uses Thermo-control technology to draw heat away from you and keep you approximately 4° cooler. It's been engineered specifically for a controlled, and precise feel, as opposed to natural fabrics that can't be controlled. It's within the DNA of the fabric to be cool, so you'll be sleeping cool regardless of how old your mattress is. It doesn't pill and is highly durable too, it's allergen-free since it's got a high elastic density.