Safety razor become locked into buying their proprietary cartridges, for as long as the manufacturer continues to make them. Subsequent to introducing the higher-priced Mach3 in 1998, Gillette's blade sales realized a 50% increase, and profits increased in an otherwise mature market. The marketing of increasing numbers of blades in a cartridge has been parodied since the 1970s. The debut episode of "Saturday Night Live" in 1975 included a parody advertisement for the Triple Trac Razor, shortly after the first two-blade cartridge for men's razors was advertised. "Mad" magazine announced the "Trac 76", arranged as a chain of cartridges with a handle
Straight razor curved lower part of the main blade from the shank to the cutting edge is called the "shoulder". The point where the shoulder joins the cutting edge is called the "heel". The endpoint of the cutting edge at the front of the blade, opposite to the "heel", is called the "toe". A thick strip of metal running transversely at the junction where the main blade attaches to the shank is called the "stabiliser". The stabiliser can be double, single, or can be absent in some razor models. The first stabiliser is usually very narrow and thicker and runs at the