Displays the percentage of charge remaining in any single 12V battery (or dual 12V/12V, 12V/24V or 12V/36V systems). Made for RVs so it comes with a “Smart-Set” feature that adapts to different battery set-ups. (Readout auto-rotates between battery one and battery two. In one-battery mode [as in, your bike] displays a steady readout.) Mounts anywhere. Only 2"×2.1"×.75", .5 oz.