SRAM XX Low Direct Mount- S3 Front Derailleur $118.95
The 20 speeds you need.
SRAM's XX 2x10 Low Direct Mount S3 Front Derailleur shares technology with its X0 stablemate, and provides crisp and precise shifts. Specifically designed to work in conjunction with SRAM's 2x10 cranksets, this XX derailleur is made to handle 39T and 42T chainrings and mounts to frames with the S3 interface.
Its cage is shorter and narrower than a triple-specific changer, which is great news for those who fear clearance issues between rear suspension and front derailleurs. The aluminum links that shape the swing of the derailleur cage have widely spaced pivots for excellent stiffness. However, the rigidity inherent in the parallelogram is part of what makes XX front shifting so quick and efficient.
The mounting types can be a bit confusing. S-series derailleurs are designed to mount directly to the chainstay. In most systems this is right at the pivot point. S3, specifically, is designed for direct-mount points that measure 22.1mm apart, center-to-center.
The derailleur cage is made from steel for maximum durability, and it's shaped for optimum efficiency with SRAM's X-Glide chainrings. The SRAM XX 2x10 Low Direct Mount S3 Front Derailleur is configured to work as either top or bottom pull options.