The MT Duo automatic chargers work with the latest SMD technology and have a charging characteristic curve according to the latest state of the art. This IUoU charging characteristic optimizes the capacity storage of AGM and gel batteries and guarantees the full performance of acid batteries with a fixed cycle due to the programmed gassing control. The chargers can be switched to the respective battery type and can remain permanently connected to the battery(s). Charge maintenance without overcharging is guaranteed and, in addition, a long-term activation program ensures monitoring-free charging. This applies not only to the main charge of the on-board battery, but also to the starter battery, as it is always supplied via a second charge output.