Hi Ulric This video is intended for Kokoda trail tours which camp up to 1900m in the tropics so a +5 degree bag in winter time is adequate sleeping attire, for the tropics regions I would use a 0 degree bag from 2000 - 2800m a -5 degree bag 2800 - 3500m and a -10 degree bag from 3500 - 4400m above that you are looking at a -17 to -20 degree bag however the time of the year will also play a big factor on this. For Kilimanjaro or Nepal treks a -17 or better bag should be used and I use a one planet -17 degree down bag with DWR water repellant coating. Hope this helps. Thanks for your comment.