Direct Mount Front Derailleurs like the X0 2x10 Low Direct Mount S1 are a godsend for frame designers and mechanics alike. Instead of aimlessly clamping to a frame, this SRAM 2x10 specific, S1 Direct Mount bolts straight to compatible frames or swing arms. SRAM's X0 2x10 Low Direct Mount Front Derailleur is specifically designed to work in conjunction with SRAM's 2x10 cranksets. As such, it's made to handle up to a 15 tooth differential between the big and small chainrings. Its cage is shorter and narrower than a triple specific, which is great news for the typically tight clearance between rear suspensions and front derailleurs. The aluminum links that shape the swing of the derailleur cage have widely spaced pivots for optimal stiffness. However, the level of rigidity inherent in the parallelogram is what makes X0 front shifting so quick and efficient. The derailleur cage is made from steel for maximum durability, and it's shaped for optimum performance with SRAM's X Glide chainrings. The SRAM X0 2x10 Low Direct Mount S1 Front Derailleur is available as either top or bottom pull and in a compatibility with either 39 or 42 tooth chainrings. This derailleur bolts straight into a E type low direct mount on your frame.