Lightweight, durable plastic composite rack for home use and long-term care facilities. For use with D, E, M9 or M7 medical oxygen cylinders, Empty racks stack easily for compact storage, Economical alternative to metal racks, Elevates cylinders from floor, Designed for patient or office use, No assembly required, ready to go from carton. Holds 8 D, E, M9 or M7 cylinder (Cylinders not included)