If you see a +20 degree score that would certainly indicate that the bag should be cozy enough for temperatures that are 20 levels or warmer.. And if you see a - 20 level score then it has actually been figured out that the bag needs to be cozy sufficient for minus 20 degree climate.
The significant difference between both styles is the cut and also form of the bags. The mummy bag is extra restricting. You can think about it like your own individual cocoon where you can go to bed in the evening as a caterpillar as well as wake up the next early morning as a butterfly. You're completed tight with not a lot of area to relocate. The rectangle-shaped bed on the other hand gets its name from its rectangle-shaped form as well as lets you relocate your legs.
Mummy bags are the tiniest resting bags as well as are very light to carry, making them optimal for those hiking trips. Lots of people could find these bags uncomfortable as they are really limiting, but they are the much better choice for outdoor camping during cool weather condition seasons because of their heat, and also hiking journeys because of their tiny dimension.