5 season sleeping bags are designed for use in cold and extreme conditions and are the warmest sleeping bags you'll find. Of course seasons can be different depending on your destination, so many people judge the performance of their sleeping bag by its comfort temperature. The comfort temperature provides a more of a universal indication of its warmth and suitability for your chosen activity and where you will be using the sleeping bag.
5 season sleeping bags (of 4+season sleeping bags) are perfect for expeditions and generally include features such as insulated baffles, durable water repellent shells and technical insulation that performs well in damp conditions to maintain its insulating properties.
This proved to be a pretty good last minute purchase. Bought just before a 2500 km trip around northern India, I found this sleeping bag fitted into my rucksack perfectly. The built in mosquito net worked well (I was hardly bitten.) Temperature wise it faired pretty well when it dropped to -10c at 16000ft but I did still have to wear thermals. All in all a fantastic sleeping bag that compresses to a convenient size
