the thumb ring and finger plates are siliconecovered to improve ergonomic handling and user comfort available in two sizes (standard and petite) and in 4 colors size petite is equipped with a smaller thumb ring and a reduced piston rod can be used with all commercially available cylinder ampoules with solid plug reliable aspiration with harpoon aspiration device side loading front part permanently attached secure handling and easy cleaning autoclavable at 134 °C or 273?°F