Comfy Splints boots have a soft fleece-lined cover that whisks away moisture. The toe post is adjustable to relieve pressure on the toes and accommodates foot sizes. It is treated with an antimicrobial surface protector to shield against mold and mildew, stains, bacteria fungus and algae. The pediatric calf circumference is up to 11 inches and can fit up to a 3.5 in a child's shoe size.