1828 sheffield made a single-sided protection blade, which is the predecessor of the safety blade. 1895, an American salesman Gillette met an inventor and painter. Painter wants to make a lot of money and invent something that everyone needs and can use once. One day, Gillette was shaving, and painter found that razor blades were just right for this idea. He designed a safe razor handle, but he couldn't find a manufacturer who could make blades. It was not until 190 1 that he met Carson, a mechanic, that he solved the technical problem, combined the hoe rest with the double-edged replaceable blade and applied for a patent. As early as 1900, the electric shaver was patented in the United States, but the first electric shaver suitable for commercial manufacture was designed by retired American army colonel Hick and patented in 1928.