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
Safety razor greatly extend their life. Disposable safety razors can be sharpened using various methods. There are commercial devices intended for this duty (Razormate, RazorPit, Blade Buddy, etc.). Myths claim that it is possible to sharpen a disposable razor by utilizing a pyramid but this is pseudoscience. Double-edge (DE) safety razors remain a popular alternative to proprietary cartridge razors, and usually offer significantly lower total cost of ownership since they are not marketed under the "razor and blades business model". DE razors are still designed and produced in many countries. Better known manufacturers include Edwin Jagger, Feather, iKon, Lord, Merkur, Mühle, Parker,