PROVIDES OPTIMUM COMFORT FOR THE LEG POSITION. SAFE, SECURE, DURABLE AND NON-RUSTY. RUBBER TREADS. IT KEEPS THE FOOT AND LOWER LEG STABLE. SIZES AVAILABLE IN 4'' ,4.50", 4.75'' , 5'' HIGH QUALITY STAINLESS STEEL. GOOD QUALITY FLEXI LINKS MADE OF STEEL NOT IRON SO MORE DURABLE