Although some people have been know to be able to adjust their derailleurs from their saddles, most of us don’t have monkey-like arms so we need Prime Gear Grapplers. These handy pieces of kit install between lengths of cable, under your handlebar, so you can adjust your gear cables while riding. They are spring loaded so they don’t loosen off while you ride and they won’t rust thanks to their alloy construction. A fine thread ensures that you can make minute adjustments and end up with perfect shifting.