Round conical/Tapered Pole,Polygonal Pole,Square Pole,Stepped Pole and High mast pole Steel Pole;light pole;lamp pole;lighting poleSpec:Raw material: Q235,SS400,Q345Welding penetration min 60%, American Lincoln welding flux, wire solder and soldering machineTaper ratio: 10/1000 to 13/1000Octagonal twisting degree max 4 degreeBig pipe can be necked max 30cm to suit small pipeMax diameter 700mm, ...