Avoid collisions and impacts during use to avoid damage to the cup or plastic, resulting in insulation failure or water leakage. When tightening the screw plug, the force should be appropriate. Do not over-rotate to avoid the screw bolt failure. When drinking coffee, tea or beverages regularly, the liner will change color. This is normal. Use a toothpaste to remove the toothbrush. Long-term use does not need to be cleaned and stored.