The Women's Patagonia Nano-Air Light Vest is made of recycled polyester ripstop shell and lining fabric that offers mechanical stretch, exceptional breathability, and improved abrasion resistance, with a durable water repellent finish. The microtexture keeps fabric from sticking to the skin for versatile comfort and the 40-gram FullRange polyester (recycled) insulation delivers outstanding mechanical stretch and air permeability (35 CFM), providing warmth while allowing excess heat to move away from the body. This articulated patterning and strategically placed, low-profile quilting, combined with stretchy fabric and insulation, provide an exceptional range of motion for unhindered movement.