Keeping you warm at the most comfortable temperature of 15 ℃ / 60 ℉. The material of the Forbidden Road Lightweight Sleeping Bag is adopted Premium Nylon in the outer which is waterproof material, plus polyester pongee used in the lining. Thus, it makes you warmer in the warm weather (Spring \ Summer \ Fall). Besides, dual zippers are designed carefully to make sleeping bag more durable. The size of single sleeping bag is 30” x 75” (75 x 190 cm), which is enough big to accommodate One adult or Two kids / children. One adult or two kids who sleep in the sleeping bag will feel roomy and comfortable. Besides, it is suitable for adult man / woman, teens, kids. It is simple to make 2 single sleeping bags into a doubled size by combining the zippers of an edge of a single sleeping bag. Besides, it is very easy to fold / unfold the sleeping bag. It takes you less than 1 minute to fold / unfold the sleeping bag. The velcro can be found at 4 corners of sleeping bag, which is very useful in folding it.