Different sizes Width X Length X Eave height Different types Single slope,double slope, Single span,double-span,Multi-spanSingle floors, Double floors Material Material Q345(S355JR) or Q235(S235JR) steel, all bolt connections. Straight cross-section or Variable cross-section. Different Purlins C or Z type: Size from C120~C320, Z100~Z200 Different roof /wall panel Single colorfull corrugated steel sheet or sandwich panel with EPS, ROCK WOOL, PU etc. All accessories Semi-transparent skylight belts, Ventilators, down pipe, Glavanized gutter, etc Surface Two layers of Anti-rust Paint!