Material -- the aluminium profile that door window of alloy of high grade aluminium profile uses, ply, intensity and oxide film wait, it is to accord with the relevant standard of the country regulation, wall thickness should be in 1.2mm above, oxide film thickness should achieve 10 micron.  

If the product exceeds the national standard, or even reaches the European standard, of course, it is the best choice.  

Performance - aluminum alloy aluminium main doors are usually assessed as follows: strength, air tightness, water tightness, open and close force, sound insulation, heat insulation, nylon guide wheel durability, open and close durability and other factors.