Tektro RL721 CX Levers These auxilliary levers fit to the tops of you drop bars and enable you to pull your brakes without having to move your hands to the drops. Tektro RL721 CX Levers are an alternative to, not a replacement for your standard drop bar levers. AKA frog levers, interrupter levers or secondary levers. Very popular on touring bikes and cross bikes (hence the CX label) where you might mostly ride with your hands on the bar tops. Come with cable adjusters - this is often the only cable adjuster available on drop bar bikes fitted with cantilever brakes. Sound forged aluminium construction. Fits bars with 31.8mm centre clamp. Works with cantilever or calliper brakes. Not suitable for V-brakes. The hinged clamp makes it easy to fit these levers directly to the bars - no heed to remove bar tape or drop bar levers. Manufacturer's published weight: 100g. While most of us believe that bar-top levers are a good thing, some riders don't because secondary levers limit the amount of space available for mounting other bar top equipment such as a light, a bell, a computer, a bar bag or a basket.