Cap incorporates LED battery and LED fuel gaugeDaylight sensor adjusts LED brightness levelFuel gauge illuminates a single green LED when full, from full to 5/8 tank a string of green LEDs, from 1/2 to 1/4 tank amber LEDs, from 1/4 tank red LEDs, and when near empty, a flashing single red LED''Empty'' fuel level at which the red LED begins flashing can be set by the riderBattery gauge shows green LEDs when the charging system is between 12.5V and 14.5V, amber LEDs if the bike is not charging and flashing red LEDs if charging level exceeds 15V or drops below 10VThe perfect match for Küryakyn's flush-mount gas cap