6 & 12 Volt Charger, Maintainer and Tester is the latest upgraded and redesigned version of our 25W Charger, Maintainer and Tester. This model features our signature State-of-the-art Pulse Desulfation Technology and can safely maintain up to two vehicle batteries connected in the same vehicle. The advanced microprocessor can easily determine battery type, size and condition to deliver the optimal maintaining for that specific battery/battery system. The 3015L Gen. 3 features a revamped and redesigned Digital Battery Tester to deliver accurate voltage readings, the AMP power to the battery and a percentage of life bar to show how healthy the battery or batteries are.