1. First of all, look at the label or instruction manual of the cup
Generally, regular manufacturers will write the product model, name, volume, material, production address, manufacturer, standard number, after-sales, use method and so on. If none of these are available, then there is a problem.
2. Identify from the appearance
Look at whether the surface polishing of the inner and outer tank is uniform, and whether there are bruises, scratches or burrs; Second, see whether the mouth welding is smooth and consistent, which is related to whether the feeling is comfortable when drinking water; Third, see whether the internal seal is tight, whether the plug and the cup match; Fourth, look at the mouth of the cup, the rounder the better, and the immature process will appear unround.
3. Tightness testing
First, twist the lid of the cup to see if the lid fits perfectly with the body of the cup, then add boiling water (preferably boiling water) to the cup, and then turn the cup upside down for two to three minutes to see if there is any water seeping out.
4. Identification of stainless steel
There are many kinds of stainless steel materials, of which 18/8 means that this stainless steel material contains 18% chromium and 8% nickel, and the materials that meet this standard meet the national food grade standards are green environmental protection products, and the products are rust-proof and corrosion-resistant. Ordinary stainless steel cup (pot) body body body color is whitish or dark, if put in a concentration of 1% salt water soaked for 24 hours will produce rust spots, it contains some elements beyond the standard, directly endangering human health.
