How the quality of insulation cup thermos to judge good or bad market stainless steel insulated cup, thermos many varieties, the price difference is very large, consumers do not understand the identification method of insulation cup is good or bad, tend to buy bad products. So how to buy high-quality vacuum flask, vacuum flask: see the appearance of a uniform surface finish of the liner and outer gall, bumps and scratches flaws; welding of the mouth is smooth and consistent, the relationship whether a drink when feeling comfortable; plastic parts quality is good or bad. Will not only affect the service life, but also affect water sanitation; four internal seals are tight. Plug and cup body with the right. Screw spin out freely, and is leaking. Filled with a glass of water upside down four or five minutes or forceful rejection of a few can verify that leakage. Insulation performance is the main technical indicators of the insulated cup. Generally the time of purchase according to the standard examination, but can be filled with hot water by hand to check insulation cup into the lower cup hot water for two minutes may have a fever, and the lower part of the insulation cup is always cool. During use to avoid a collision and impact, so as not to damage the cup or plastic, resulting in insulation failure or leaks. Force when the twist tight plug should be appropriate, do not over-rotating, so as not to screw buckle failure. The regular consumption of coffee, tea or drinks, the liner will change is a normal phenomenon, toothpaste, toothbrush to clear.