Flannel:Flannel is a material most people are likely familiar with from flannel shirts, but it is also a material used for bedding. Traditionally only made with wool, flannel is now made with a variety of materials. Cotton and polyester are the most common.
Crafted with naturally long fibers, bamboo is super-durable and is unlikely to pill or tear. And, as it doesn't absorb moisture (unlike cotton), it won't take on natural oils from your skin, meaning it's less likely to discolor and more likely to last longer.