Remember that with time, from typical use, a treking sleeping bag will certainly lose its warming performance. This results from the fill obtaining a bit much more compressed. This will cause the "air pockets" to go away.
Children's: These primarily have "Youngster Friendly" connects as an example: pockets for their "stuff", a pocket to stuff and also make a cushion at their head and a resting pad restraint system to make certain that the pad stays in place all evening.
Rectangle-shaped sleeping bags go as much back as the late 1800's when a mail order catalog pioneer Pryce Pryce-Jones came up with the suggestion to attach 2 rectangular carpets together with ties. He is taken into consideration to be the innovator of today's contemporary rectangular sleeping bag design. After the war he had several of these bags still left as well as made a decision to market them to the public.