These slippers are a perfect fit for my 7.5W sore feet. The insole is cushioned evenly so there are no pressure spots. The instep is flexible so the sizing of 6.5-7.5 should not be a problem. They have wool (soft, insulating, breathing) and some other soft fibers and a non-skid sole. The darker color means they won't need to be washed as often and I really like that I can wash them.