
High-Strength Prestressed Flat Tube for Concrete Duct Systems. Customizable Length: Standard 5.8m per piece with fully customizable length options available. Galvanized Steel Material: Made from hot-dipped galvanized steel strip for superior corrosion resistance. ISO 9001 Certified: Manufactured under strict ISO 9001 quality management standards. High Radial Stiffness: Features excellent radial stiffness and leak-proof performance for safety. Free Sample Availability: Samples provided free of charge, buyer covers express shipping costs. In-House Manufacturing: Fully produced in-house at our own factory with 120+ employees. CE & IATF16949 Certified: Holds CE, ISO, and IATF16949 certifications for global compliance. Fast Delivery Time: Normal delivery within 20 days after deposit or L/C receipt.