Review extrusions look good or bad of a few key points
in the first place, of course, is to see whether the aluminum on the exterior shape distortion, touching the surface is smooth and flat, if there is any crack or bubbles, scratches, burrs and smooth. If found to have had better not buy, this is the most obvious quality problem. Second, is to examine aluminous profile surface color, whether there is any color difference. There are color difference quality closes nevertheless. Aluminum profile or you can put the same type of material together to compare, if the color difference is too obvious also had better not to choose and buy. Also, check whether the section thickness of the aluminum and tagging model, whether there is have different physical and annotation. Finally, just can use to draw a smooth hard objects under the surface of the aluminium profile, leave when a white scratches. We use hand gently wipe and observe, if not erased, illustrate the potential quality material has a problem, if you can very easily erased, it is indicated that the thickness of oxide film on the surface of the material is qualified.