Ansmann Comfort Smart PERFECT 7 NiMH Battery Chargers - Ansmann 1001-0092, The Ansmann Comfort Smart battery charger is the next level in NiMH charging technology. The good people at Ansmann have developed the Perfect 7 technology as a safer and more efficient way of charging your NiMH batteries, prolonging your battery's life as well as using USB power for the charging source. At the start of charging the charger will check the battery and if the charger thinks the battery is not up to scratch it will flash red to let you know that the battery is no good. After the charging is complete the charger will give a gentle pulsed trickle charge, making sure your batteries are ready when you need them. A clever feature of the charger is that if the USB power supply doesn't give sufficient current for the charger to fully operate, the charger will put the process on hold for one or two of the batteries (with an orange flashing light) and charge those once the others are fully charged Ansmann 1001-0092 Comfort Smart Battery Charger