Makers of Battery Chargers / Maintainers / Desulfators-Conditioners. VDC Electronics' BatteryMINDer products are uniquely capable of extending the life and performance of all type/size/brands of 12/24/36 & 48 Volt batteries by as much as 300%. They are all guaranteed never to overcharge your battery, regardless of time. They are designed to restore/recover older batteries and keep new ones living longer. U.S. Patented circuitry safely dissolves sulfate, the #1 source of early battery failure and loss of performance. All units are guaranteed to perform as advertised or VDC will refund 100% of your money within 1 year. This is in addition to their 5-year "no hassle" limited warranty.