Preservation pulse charge extends battery life and preserves battery power. The device can permanently be connected and is thus suitable for seasonally used vehicles. Automatic shutdown when the battery is fully charged. 4.2 ampere charging current. High efficiency of up to 85%. Compact dimensions and easy operation ensure practical use. For all types 12 Volt 4 to 120Ah lead acid batteries (wet, gel, MF and AGM) and lead-calcium batteries.