There is a big difference between voltage indicators and the Curtis 24-Volt BDI Battery Gauge. BDI stands for battery discharge indicator. While a standard voltmeter would show you a live voltage reading, it does nothing for telling you how much run time you have left. A BDI takes a base reading of the voltage when the cart is fully charged and then bases its indication on discharge rate. For example, a voltage indicator would tell you that you had 24.5 volts in your 24-volt system. What it does not show you is that your batteries are almost dead at that reading.Golf carts run on overcharge. If you have a new set of batteries on a 24-volt system, fully charged, the entire pack should read almost 30 volts. The buggy runs on that six volts of overcharge all day. This is why a Curtis 24-volt BDI battery gauge is the best option for making sure you know how far you can go. Call Buggies Unlimited today.