Hexagon backnut No. 21 made of steel Material: steel, black or zinc plated Thread: ISO 7-1 Working Pressure: PN 50 Available options Available Options: You may also like… Select optionsThreaded flange EN 1092-1 Typ 13 (DIN 2566) Choose optionPipe nipple, taper thread both ends No. 23 – 1″ to 2″ Choose optionPipe clamp with EPDM profile Choose optionAnaerobic thread locking