Feature:  high precision, good brightness,                 no oxidize residual, could withstand high pressure,                 no deformation after cold bending,                 no crack and break after flattening and flaring,                 good mechanical property and no deformation after bending at any angle.   1) Description: Cold-drawn or cold-rolled high precision seamless steel tube   2) Brandname: XINGYU   3) Grade: 10#;20#;16Mn; ST30Al;ST35; ST37;ST37.4;ST45;ST52;ST52.4;etc.   4) Standard: ASTM A519;ASTM A106 ;JIS; DIN2391; DIN 1629;DIN1630,DIN 73000;EN10305-1 or any other equivalent stardard   5) Specification: Outer Diameter: 4mm-50mm;                                Wall Thickness: 0.5mm-5mm   6) Diameter tolerance: 0.05mm (Enterprise internal control) or                                          0.03mm(Special high-precision)   7) Length: 4-12 Meters   8) Surface treatment : 1. Bare Tube (No coating)-Bright and smooth; Surface Roughness: BK<0.2Ra; NBK<2Ra 2. Surface coating          a.silver galvanized          b.yellow galvanized          c.olive green coated 3. Black and Phosphated Layer thickness:8-25um; saity spray test: 48-150 hours 9) Process method: Cold-drawn or cold-rolled 10) Packing: wrapped with PVC and gunny sacks 11) Basic Inspection:  Chemical analysis and mechanical testing 12) MOQ: 1 MT 13) Delivery time: 45 days after 30% deposite;                                 or upon receipt of relevant L/C 14) Production capability: 300 MT/month 15) Payment method:T/T; L/C;  Other electric payment such as paypal 16) Certification: ISO9001: 2008 17) Application: Automotive pipeline system; hydraulic system of diesel engine and engineering machinery; hydraulic system of locomotive, aerospace and aviation, shipbuilding and various machinery; metal processing of wind power equipment; etc.