... and pressure applications and is also acceptable for ordinary uses in steam, water, gas, and air lines. ASTMA53 tubes ConditionO.D.W ... : usually 1mm, best within 0.5mm, we will offer best for you.Chemical composition: %(Max.)CMnPSCrNiCuMoVGrade A0.250.950.050.0450 ... ! ASTMA53 tube/Hot dipped zinc coated seamless pipe /Column pipe for water pump