Our ISO63 NW Thick Wall Stainless Steel Bellows Flexible Hose follow ISO standards. The wall thickness = 0.25mm. They are commonly used to build vacuum systems with a vacuum level < 10E-8 mbar/Torr. Individual double claw clamps and centering ring form the vacuum seal between the connecting flanges. The centering ring contains a rubber elastomer o-ring. The standard sizes for ISO flange fittings are ISO63, ISO80, ISO100, ISO160, ISO200, ISO250, ISO320, ISO400, ISO500, ISO630 with bore sizes NW63, NW80, NW100, NW160, NW200, NW250, NW320, NW400, NW500, and NW630 respectively. They are made of corrosive resistant 304L stainless steel and have a thick wall, ideal for vibration absorbtion and mis-alignment.