The Occipital Rings are neck supports designed for head, neck, trunk, and shoulder support during wheelchair use. The ring is made of high-strength aluminum alloy and covered with high density tubular foam and a Lycra form-fitting slip cover. The hinge bracket at the back of the ring is designed to interface with the swivel tube hardware for use on a wheelchair. SIZES: Available in small child, large child, small adult and large adult. DIMENSIONS: The width between the support tubes is 3.5 inches for a small child, 4.25 inches for a small adult, 4.75 inches for a large child, and 5.5 inches for a large adult. The length of the child's occipital ring is 7.5 inches divided between a 3-inch horizontal section and a 4.5- inch angled section. The adult occipital ring is 10 inches long divided between a 4.5- inch horizontal section and a 5.5- inch angled section.