Teaches elementary crawling skills to children with developmental delays. The unique design properly aligns the child's body while encouraging crawling motion and weight bearing on hands and knees. Sling height is adjustable from 9 -17" (22.9 - 45.2 cm) to accommodate various sized children. The body of the crawler is made of lightweight durable plastic and weighs approximately 20 lb. (9 kg). Factory-installed casters are out of reach from children's hands. Weight capacity is 175 lb. (79.6 kg). Optional handrail kit (purchase separately is available as an accessory to transform it into the Sit and Ride Ambulatory Aid.