Square lead helical piers 1 1/2 inch Square Bar,1 3/4 inch Square Bar,2 1/4 inch Square Bar Bar Material: 40Cr or 45# steel, round corner 5mm radius Helix Plate material conforms to ASTM A36 hot rolled plate helices thickness are available in 3/8inchand 1/2inch All helix leading edges sharpened and rock cut and 45 degrees Corrosion protection to conform to ASTM A153 standard for hot dipped zinc coating A better conventional solid steel extra high strength helical screw pile Welded coupling for greater strength. Eliminates shaft heat damage caused by upset coupling process OEM service is available, different materials and specifications can be customized according to your demands. We have our own factory here in China and quality meeting the specifications of our buyers, our prices are also very than your present buy. Forklift Solid Tire