When choosing a sleeping bag important factors to consider are the bag's season, rating and its comfort and extreme rating. The season rating on a sleeping bag is shown in number form; 1 or 2 = summer, 3 = spring/autumn and 4 = winter to help you choose the appropriate bag depending on the season you'll be completing your expedition. A 3 season bag is recommended for those completing the Bronze, Silver and Gold Awards. The comfort and extreme rating on the bag will indicate the suggested temperature range wherby the bag will perform. We have put together a range of sleeping bags from Vango and Snugpak that we recommend for those participating in D of E.