4.2 Appearance requirements should comply with the provisions of Table 2. Table 2 Appearance Requirements No. Item Appearance Requirements 1 Aluminum profiles Aluminum profiles should be smooth and clean, without cutting stubble, burrs, defects, cracks, or dents; there should be no fading or discoloration on the surface 2 The back and side panels of the aluminum plates should be smooth and smooth, without any There should be cracks and no obvious scratches. The plates should be cut neatly without burrs; there should be no fading or discoloration on the surface. 3. Edge sealing treatment: The adjacent surfaces of the aluminum plate components should be edge-sealed. There should be no degumming, bubbling or glue leakage at the edge sealing area. , exposed bottom 4. The coating should be free of spray leakage, rust, smooth and even, consistent in color, and should have no defects such as sagging, pimples, wrinkles, flying paint, etc. 5. Fasteners, hardware accessories and connectors should be free of damage, rust, and burrs. , sharp edges 6. Other parts that come into contact with the human body or collected items should be free of burrs, edges, and corners; the product should be firm and should not have deviations, looseness, falling off, etc. 4.3 Hazardous Substance Limits Soluble heavy metals in product coatings should comply with GB 18584 Regulations on limits of hazardous substances.