Made from mild steel bent into a spiral shape and treated for outdoor use. Can be used in conjunction with 9x 500ml or 300ml Rapid Grow Pots. Made to hang with a hook off trees or anything that will support it. Perfect for most flowers, vegetables, herbs and decorative plants . Rapid grow pots can hold plants 40-70% bigger per volume then conventional pots allowing for a wide range of plant options. For indoor use black moisture retaining cups are recomended to lower maintenance and eliminate mess