Razor be used on both sides, with two open edges. The blade on the double-edged safety razor is slightly curved to allow for a smoother and cleaner shave. In 1901, the American inventor King Camp Gillette, with the assistance of William Nickerson, patented a new variation of safety razor with disposable blades. Gillette realized that a profit could be made by selling an inexpensive razor with disposable blades. This has been called the razor and blades business model, and has become a very common practice for a wide variety of products. Many other brands of safety razors have come and gone.
American Safety Razor Company and blade production remained in Brooklyn. By 1921, it had produced 1,800,000 safety razors; 110,000,000 razor blades; 1,000,000 shaving brushes; 2,000,000 cakes of shaving soap. By 1942, it had introduced and popularized the phrase "five o'clock shadow". In 1953, it acquired the Pal, Treet and Personna brands after purchasing the Pal Blade Company. These two product names continue to be made today. In 1954 the factory relocated to Staunton, Virginia, after the Brooklyn City Planning Commission's planned civic center encroached on the factory with plans to redevelop the industrial area into office and residential use. The American Safety Razor factory