Walmart offers the Schumacher XM1-5 1.5-amp Maintainer Vehicle Charger for $25. Opt for in-store pickup to avoid the $4.97 shipping charge. That's tied with last week's mention and the lowest price we could find by $6. This microprocessor-controlled battery charger features a quick-disconnect harness, automatic voltage detection, temperature compensation, reverse hookup protection, and LED charging indicators.