Capable - wide enough gear ratio and good gear step optimized for from steep climb to fast decent. Keep pedaling in efficient front driving gear with wider range cassette for riding up and down through trails. Low gear option for wide tire trend (27.5 Plus) and women and youth.
Efficient - smooth shifting of front and rear in rhythm in order to maintain speed and acceleration in change of terrain. Less loss of pedaling power by rigid structure with easy and effortless shifting operation.
Reliable front shifting even when the rear suspension moves.