Anyone who has ever slept in a sleeping bag or worn an insulated hoody will know the insulating power of down or synthetic insulation. These warm sleeping systems and toasty puffies are the very definition of cozy. In the case of insulated jackets, they've become really quite fashionable too. These days, the catwalk is no stranger to a puffer.
The magic happens on the inside, where an insulating material traps air that's then warmed by your radiated body heat. This is what gives a puffer or sleeping bag it's glorious warmth. This material is either down, a natural material taken from ducks or geese, or a synthetic material, usually polyester.
