1. Low alloy high strength structural steel Q235B and High Frequency Welded Light Gauge H sections 2. Size:70*50-500*250 ... frequency welded light gauge H Sections for contruction 1.standardGB/T 1591, GB/T700, ASTM, EN, DIN2. Steel gradeST37, A36, SS400, ... all kinds of architecture and engineering structure, such as the beam, Bridges, transmission tower, lifting transportation machinery, the ships, ...