52 mm ROUND STATE OF CHARGE METER. New!! All of our meters are made in the U.S.A. These meters work on lead-acid batteries only THIS METER COMES WITH MOUNTING HARDWARE TO MOUNT IN 2 1/16" HOLE. THIS BATTERY METER ALLOWS YOU TO SEE HOW MUCH CHARGE IS IN YOUR BATTERIES AND WHEN THEY NEED CHARGING. DON'T GET STUCK RUNNING OUT OF POWER, INSTALL A BATTERY GAUGE TODAY. INSTALLATION IS VERY EASY, ONE POWER AND ONE GROUND WIRE TO HOOK UP TO THE STANDARD 1/4" SLIP-ON ON TERMINALS. METER MOUNTS ANYWHERE, MEASURES 2-3/16''O.D. X1-3/4 DEEP. FITS ALL CARTS WITH 36 VOLT SYSTEMS Give us a call M-F 9-5 est 727-572-9011