They are like a sleeping bag, but because they have an open back, they save quite a bit of weight. They have straps so you strap them to the sleeping pad/air mattress. This way, you are still insulated 360°.
The basic idea is that in a sleeping bag, because you compress the material below you, that material doesn’t really insulate anyway.
I don’t get what they are good for. What is the use case?
They are like a sleeping bag, but because they have an open back, they save quite a bit of weight. They have straps so you strap them to the sleeping pad/air mattress. This way, you are still insulated 360°.
The basic idea is that in a sleeping bag, because you compress the material below you, that material doesn’t really insulate anyway.
Also some people find them more comfortable than bags