Even in the summer, temperatures can rise sharply after dark That's why we keep the Neutrino Pro 500 sleeping bag in our mountaineering kit for three-season comfort. The narrow silhouette of the bag and the chevron-shaped partition help reduce the weight of the backpack as much as possible , and down with a density of 800 units guarantees that after sunset we will be as warm as possible. Weather-resistant hydrophobic down and water-repellent recycled nylon prepare us for summer storms and alpine snow.