Because camp in a wide variety of temperatures and I sleep relatively cold, I had setups for warm, shoulder and cold seasons. Because of the versatility of the Puffle, I can customize the temperature rating by stacking my 55F Vegan and 40F down Puffles. The 40F down packs to about the same volume as the 55F Vegan which is very small. They are a great fit for the Ninox as an under quilt. They allso make a great top quilt, either stacked or by themselves.When they are not being used for camping, the Puffles are great for lounging around the house.