The Tarius -5 Regular Sleeping Bag has a normal mummy shape around the main body to give you space to move around while the hood & footbox are ergonomically shaped in order to keep you as warm as possible & reduce the chance of any drafts. The zip opens three quarters of the bag & at the shoulder it curves towards the hood opening to make it easier to open & close when you are in the bag. There is also an internal pocket to allow you to keep valuables safe & secure while you sleep.