Fire eye expander 40t sprocketfully cnc machined rear cassette sprockets from fire eye features material aluminum 7075 t6 compatible with 2x10 or 1x10 drivetrains shimano model suitable for shimano xtr m980 11 36t xt m771 10 11 36t sram model suitable for sram x5 pg 1030 11 36t x7 pg 1050 11 36t x9 pg 1070 11 36t weight 72g 40t 79g 42tbuyfire eye componentsfrom chain reaction cycles the worlds largest online bike store