We are offering Carbon Steel Cold Drawn Seamless U Tube for Heat Exchanger.Standard: ASTM A 556 SA 556Size: OD (10-76mm) x WT (1.5-5mm) TEMA CODE (U Tube used in Heat Exchangers) (U Tube used in Tubular Feed Water Heaters)Application: Seamless Cold-Drawn Low-Carbon Steel tubes for Heat-Exchanger and Condenser. Heat Exchanger TubesStandard: ASTM A179ASME SA179 Size: OD (10-76mm) x WT (1.5-5mm) TEMA CODE (U Tube used in Heat Exchangers) (U Tube used in Tubular Feed Water Heaters)Application: Seamless Cold-Drawn Low-Carbon Steel tubes for Heat-Exchanger and Condenser.