NameHot rolled black surface steel round bar 4340 alloy steel Features 1, chromium molybdenum alloy steel; 2, high strength and toughness; 3, good stability of hardenability and anti-overheating; 4, good high tensile strength with shock resistance. Applications 1, heavy machinery and high-load of shaft; 2, rotor shaft and blades; 3, special performance requirements of the vital parts after nitriding treatment. Sizes Round bar Diameter(mm) Length(mm) Max 800 Max 9000 Plate Thickness(mm)Width(mm) Length(mm) Max 800 Max 2200 Max 9000 The above is our regular size, we also can provide customized sizes! Packing 20ft: gw 27t; (5.80mx2.13mx2.18m) 40ft: gw 27t; (11.8mx2.13mx2.18m) PriceThe price will change according to the weight of the steel you need. C Si MnP S Cr Mo Ni 0.38-0.430.15-0.350.60-0.80Â?¤0.035Â?¤0.0400.70-0.900.20-0.301.65-2.00 Why can i believe your steel? 1, all products must pass the following quality tests to meet you requirments! 2, our steel has passed the following certificates! 3, providing all kinds of cutting service for you! 4, there are 50, 000 tons in our stock! Suitable for sea delivery or based on client's request Note:20ft: gw:17.5t; (5.80mx2.13mx2.18m, ) 40ft: gw:22t; (11.8mx2.13mx2.18m, )