Improved chain guide shape delivers smooth shifting at each rear position, even under heavy load Stiffer, wide inner link design with two pivots increases strength, rigidity and eliminates the need to manually trim the outer chainring - no more chain rub in the big-big combination! DUAL SIS front indexed shifting with optimized spring tension reduces the shifting effort required to move between chainrings - the result is featherlight downshifts and smoother upshifts Forged aluminum construction lowers weight without sacrificing durability Use with Shimano Dual Control Levers for both small and big ring trim The new Shimano 105 5700 Front Derailleur provides even smoother shifting performance than before. It features dual SIS front index shifting, a wide inner link design and an improved chain guide shape that delivers smooth shifting at each rear position, even under heavy loads.