Safety razor entitled "Fuck Everything, We're Doing Five Blades" predicted the release of five-blade cartridges, two years before their commercial introduction. South Korean manufacturer Dorco released their own six-blade cartridge in 2012, and later released a seven-blade cartridge. Gillette has also produced powered variants of the Mach3 (M3Power, M3Power Nitro) and Fusion (Fusion Power and Fusion Power Phantom) razors. These razors accept a single AAA battery which is used to produce vibration in the razor; this action was purported to raise hair up and away from the skin prior to being cut. These claims were ruled in an American court as "unsubstantiated
Safety razor professional) and remained a barrier to the ubiquitous adopting of the "be your own barber" ideal. The first safety razors used a single-edge blade that was essentially a 4 cm long segment of a straight razor. A flat blade that could be used alternately with this "wedge" was first illustrated in a patent issued in 1878, serving as a close prototype for the single-edge blade in its present form. New single-edge razors were developed and used side-by-side with double-edge razors for decades. The largest manufacturers were the American Safety Razor Company with its "Ever-Ready" series, and the Gem Cutlery Company