Material: high quality 45 # steel diameter tolerance: f7-f8 (other tolerances can be custom-made) surface roughness: Ra0.2-0.4 hard chrome thickness :0.015-0 .025 mm surface hardness: HV700-1150 a straightness 0.05 - 0.10 m / m standard length of 1-6 meters and the other can be customized surface treatment by high wave depth of 1-3mm high wave hardness: HRC45 ° C to 52 ° C Note: According to different purposes chrome thickness: Pressure = 0.02mm hydraulic = 0.02mm above http://www.rekong.com/ProductShow-25-3.html recommend: film blowing machine; http://www.fsxiexiang.com/ glass mechanical http://www.cnlinshi.com/ProductList.html of