High quality 304 stainless steel with a chrome finish, Not nickel chrome plated like most other available on this site. High quality metal work, no weld spots, rough edges or cheap fabrication Perforated tip to allow fluids to pass and airflow and comfort Super-strong cage , Probably the smallest available on the market! Unique hidden style screw lock - we even supply the tool to lock/un-lock it Ergonomic comfort style Back with a diameter of 45 mm