Blind cup A cup designed for the blind

Some people may wonder how there are blind people in the cup. If you close your eyes and pour water into a glass, I expect many people will overpour the water, because it is difficult to know when the water will be full. So this blind cup is aimed at this problem, specially designed for the blind cup. There are three indicator lines on the handle of this cup, and there are three water level sensors in the cup accordingly. The blind person only needs to hold down the indicator line of the amount of water needed, and then pour water at will. When the water reaches this level, it will make a sound, and then stop pouring water, and there will be no overflow of water.