SRAM MRX 8 Speed Twist Shifter (Rear) 2:1 Shimano Compatible The MRX ergonomic shifter is the original Grip Shift shifter that has sold in the millions across the globe because of its entry level price & compatibility with DIRT & Shimano derailleur systems it is now available with some of the new technology Ergonomic hex-profile shifter cover with soft density grip SRAM composite construction Completely enclosed cables seal shifter from contaminates Easy cable change grip cover