SRAM Red Rear Derailleur - 11 Speed Short Cage BlackSRAM Red Rear Derailleur 11 Speed Short Cage Black. Top of the line rear derailleur with generous use of carbon fiber and titanium for maximum performance at minimal weight. Carbon fiber and aluminum construction Ceramic bearing pulleys Titanium hardware TECH SPECS Rear Derailleur Mount Type 10x1 Standard Rear Der Shifter Compatibility SRAM Exact Actuation Cage Length Short Drivetrain Speeds 11 Weight 145 Color Black keyword search RD4620 Chain Wrap