Battery Tender 022-0142-DL-WH Power Tender Plus 12V Compact Charger Delivers 12-volts output at 5.0-Amps or 2.5-Amps featuring switchable power levels Four step fully automatic charging - initialization, bulk charge, absorption and float Spark proof even when output leads touch 72 hour safety timer protects marginal batteries from further damage Reverse polarity protection eliminates charger or battery damage