BOX One Prime 9 Multi Shift Shifter - 9-Speed BlackPrime 9 Technology for greater simplicity and durability Available in single shift option for eMTB to keep the user from shifting multiple gears under load, significantly reducing the rate of bent teeth and broken chains Multi shift option changes up to 3 gears at once for non eMTBs Box One features: diecast top shell, machined clamp, diecast release lever, and a stainless braided lo friction cable Box Two features: diecast top shell, and extruded