The 100% organic cotton is woven in twill, which consists of two pieces of long-fiber yarn twisted together. This makes the material extra strong and durable. The surface is finally brushed on both sides, giving flannel its soft and refined quality. These nightwear pants are suitable for use during the winter months as they are both insulating and comfortable. As our Oslo nightwear is made in the same exclusive quality as the rest of our range, it also comes with a 10-year quality guarantee.