Razor razors were the most common form of shaving before the 20th century and remained common in many countries until the 1950s. Barbers were specially trained to give customers a thorough and quick shave, and a collection of straight razors ready for use was a common sight in most barbershops. Barbers still have them, but they use them less often. Straight razors eventually fell out of fashion. Their first challenger was manufactured by King C. Gillette: a double-edged safety razor with replaceable blades. Gillette's idea was the use of the "loss leader" concept, in which the razors were sold at a
American Safety Razor Company building at 333 Jay Street then became the new campus for the Polytechnic Institute of Brooklyn. Seeking diversification Philip Morris acquires American Safety Razor in 1960. In 1963 American Safety Razor is the first maker of stainless steel blades, which were sold under the Personna brand name. In 1968, Philip Morris, purchased the Burma-Vita Company, makers of Burma-Shave. In 1970, the first blade made with tungsten steel was introduced, the Personna 74. In 1974 American Line Brand of industrial products was introduced, expanding the company into industrial blades. In 1977, executives purchased Personna American Safety Razor Company from Philip Morris