Sanitube's polished tube is manufactured in accordance with ASTM A270 and 3A sanitary standards. Our tubing is made from cold rolled stainless steel strip whose chemical elements are specially controlled to enhance weldability. The weld bead is cold-worked to a full finished condition, resulting in a virtually undetectable longitudinal weld. Bright annealing to 1,900°F minimum follows in a controlled atmosphere to preserve maximum structural integrity. The tubes are then mechanically polished to a 180 grit (20 μ-in. Ra maximum) interior and 150 grit (32 μ-in. Ra maximum) exterior finish via Sanitube's state-of-the-art process. Tubes are then line-stenciled with OD, wall, ASTM specifications, grade, and heat number. Price and weight is per foot.