Fittings are double ferrule for leak proof, torque free seal at all tubing connections. Fittings confirm to ANSI 31.1,ANSI 31.2,ANSI SEC VIII and BS 4368 etc as per various special industrial requirements. Each identifications are provided, such as step shoulder on hex nuts. Range :1/8"OD to 1"OD, 4mm OD to 25mm OD End connections :BSP/NPT/BSPT MOC :SS 304, SS 316, MONEL, HASTALLOY, TEFLON, CS