This is a great mummy style sleeping bag, with the added flexibility of being more roomy than a tradition mummy with the two zippers. I bought a regular size for my husband who is 6ft tall, 185lbs, and it is tight if he wants to sleep on his side. Probably should have sized up to a long, but we’ll make this one work. It’s very warm and comfortable, and stuffs amazingly small for such a warm bag. We’re using this for back packing 2-3 day trips in 30-60 degree weather, and it’s so much better than our older heavier bags. Would highly recommend!