All of the sleeping bags that I own are the lightweight packable type of bags. None are very thick or rugged so these sleeping bag liner sheets come in handy to make camping warm and cozy. The fold and roll tight right into a storage bag so I usually just tuck them right into the sleeping bag for transport.
They are good for traveling too in case the kids fall asleep in the back seat of the car on a long drive. These sheets are large enough to cover them both with room to spare. I keep them in the trunk of my car just in case. They could also serve as a picnic blanket in a pinch. https://www.amazon.com/dp/B01LWT5NFI #YUEDGETravelAndCampingSheetSleepingBagLiner