My first night with the Downwool Ice was in a tent in the Alps in winter at -14 degrees Celsius. My shoes and water bottle froze overnight in the tent, but I still had a comfortable and restful sleep.

The Extreme Light has been the one I've used the most so far; it's simply perfect for bivouac tours in the open air in summer or overnight stays in bivouac boxes. I spent several nights in a tent with the Extreme Light on Madeira and am always surprised by how good the sleeping climate is. In recent years, you had to bring a proper sleeping bag to Alpine Club huts for hygiene reasons, as blankets were no longer handed out. Thanks to its small pack size and low weight, it has been a faithful companion on many overnight stays in huts and can also be easily taken along on alpine tours with a lot of other equipment. The smart zipper allows you to regulate the temperature really well so you're neither too warm nor too cold. The tour that has stuck in my memory most was an overnight stay in a bivouac box in the Bavarian Alps in October.

It was freezing outside overnight. The bivouac box was quite large for two people, poorly insulated, and without a stove, so it was correspondingly cold at just under 2000 meters. This might not have been the ideal use for the Extreme Light, but the first rays of sun at sunrise made it all the better!