CTEK (56-958) MUS 4.3 POLAR 12 Volt Fully Automatic Extreme Climate 8 Step Battery Charger Specially developed for use in extreme cold conditions featuring AC and DC cables adapted to handle severe cold temperatures Fully automatic 8 step patented program tests battery condition and revives, charges and maintains to ensure maximum battery life and performance No sparks, short-circuit proof and reverse polarity protected makes it safe for all the vehicles electronics and easy to use Water and dust resistant means it is safe to use in all climate situations Numerous accessories simplifies using the same charger for multiple battery applications