Lead acid battery capacity indicator: provides a clear reading of remaining charge for lead acid batteries, helping you manage charging and plan usage without guesswork. LED bar display: shows capacity with five LED bars in three colors (1 red, 1 yellow and 2 greens). Each LED bar increases from E to F to indicate progress from empty to full. Compatible voltage: suitable for 12V, 24V, 36V, and 48V systems. performance and protection: waterproof battery capacity indicator with reverse connection protection, designed for reliable operation and easy installation. Use scenarios: Electric vehicles and marine applications: monitor the battery level on golf carts, boats, or small EVs that use lead acid packs. Offgrid and longlife systems: keep track of battery status in solar, RVs, or cabins with lead acid storage to avoid unexpected power loss. Backup power and workshop use: manage standby power supplies and equipment that rely on lead acid batteries, ensuring timely recharging and maintenance.