These jeans will keep you warm! The Five Brother Relaxed Fit Flannel-Lined Denim Jean offers top-of-the-line durable protection. Like the unlined version, the flannel-lined outer is made out of a pre-washed 14 oz. cotton denim that is resistant to tears and rips. The inner lining, from the waist down, is made of 100% cotton flannel. Additionally, the classic five pocket design includes deep set front and back pockets for rulers and coins, double needle stitching and can be easily cleaned through machine washing and drying.