Amazon Essentials Men's Flannel Pajama Pants - Soft & Comfortable Sleepwear for Big & Tall - Perfect for Lounging, Sleeping & Cold Weather Comfort

Bought these for my dad and liked them so much for their softness and comfort, I kept a pair for myself. Also, Amazon had them on sale which is why I tried them in the first place. Very good choice as they are comfortable and warm without being too heavy.