Adjustable rings serve as stops or mounts on the tube: as a classic adjustable ring, with an eye (14 mm hole), with a pin (12 or 13 mm), or with a hook. Made of hot-dip galvanised malleable iron with a stainless steel clamping screw. For tubes with diameters of 26.9 / 33.7 / 42.4 / 48.3 mm.