Shimano deore m590 9 speed trigger shifter setdeore mountain bike rapidfire shifter pods featuring 2 way release for cost effective 9 speed shifting performance features2 way release allows shifting from various riding positions the upper lever still performs the same shift function but it can now swing in either direction allowing it to be released by the thumb or index fingermega9 compatible for use with precision 9 speed drivetrainpod design allows the use of these shifters with any brak