1. Check the material markings: High-quality products will clearly indicate "304/316 stainless steel." You can use a magnet to help determine the material's quality (304/316 has weak magnetism, while ordinary ferritic stainless steel has strong magnetism). Be cautious of products with no markings or blurry markings.
2. Check the surface finish: The surface should feel smooth to the touch, without burrs or a rough feel. Brushed finishes have a uniform texture, while mirror finishes have a delicate sheen. The surface should be free of bubbles, pinholes, or color variations. Inferior products are prone to oxidation spots.
3. Inspect the welding and joints: Joints should be fully welded without any gaps or looseness. Screw holes should be neat and without stripped threads. Inferior products may have cracked welds or loose joints.
4. Test corrosion resistance: Check the product's testing report (e.g., passing the salt spray test). Alternatively, wipe the surface with a paper towel soaked in salt water. High-quality products should show no rust or corrosion after 24 hours.