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.
Segal Lock and Hardware Company stock was placed privately with no public offering made. The company acquired a controlling interest in the Norwalk Lock Company and the Universal Razor Blade Corporation in 1929. Stockholders approved an increase in the authorized stock of the company to 400,000 shares, of which 300,000 shares were outstanding. The corporation introduced a single-unit safety razor in late 1930, a low-priced product designed to use only Segal double-edged blades. The following year Segal placed on the market the Unimatic Segal Razor, a one-piece razor which accepted a double-edged blade. The firm entered a contracted with United Cigar Stores in June 1931.