Brake levers are usually mounted on the handlebars within easy reach of the rider's hands. The brake lever transmits the force applied by the rider through either a mechanical or hydraulic mechanism. Bicycles with drop handlebars may have more than one brake lever for each brake to facilitate braking from multiple hand positions. Levers that allow the rider to work the brakes from the tops of the bars, introduced in the '70s, are called extension levers or safety levers. The modern equivalents are called interrupt brake levers and are considered superior Mechanical (cable) brake levers come in two varieties based on the length of brake cable pulled for a given amount of lever movement, Standard pull levers work with most brake designs, including calliper brakes, traditional cantilever brakes, and mechanically actuated disc brakes branded for "Road". Long pull levers work with "direct-pull" cantilever brakes, such as Shimano "V-Brakes, and mechanically actuated disc brakes branded for "Mountain". Direct-pull levers are generally unsuited for use on drop handlebars. Please also see Gear Levers and Shifters as these integrate brakes into the shifting mechanism.