From canoeing along the pristine lakes of Northern Wisconsin to dodging rain showers along North Carolina's Blue Ridge Mountains, the Mammut Machu Drytech Hat provides waterproof protection from passing storms while breathing well to keep you from overheating in summertime. Mammut employs their DRYtechnology 2. 5-layer membrane inside the hat, which provides a 10k/10k waterproof, breathability rating. Ultimately, this DRYtechnology means the Machu will bead off passing showers with ease and allow excess heat to escape through the membrane's microscopic pores. It's even lined with moisture-wicking mesh, so you don't succumb to excess sweat build-up inside the hat. And to ensure a secure fit, the Machu Hat uses an adjustable drawstring to keep it from falling off as you paddle downstream or hike down the trail.