The fsa energy bb30 stages power meter upgrades an array of fsa bb30 crank options with power the stages power meter is mounted to fsas hollow forged energy alloy non drive crank arm the bb30 version has across the board compatibility with fsa and vision bb30 modes note the stages power energy bb30 will not fit any bb386evo modelsspecifications accuracy 2 weight only adds 20gr to base crank arm battery life 200 hours coin cell cr2032 power range watts 0 2500 cadence range r