This fast bicycle battery charger is specifically designed for charging Bosch Li-Ion batteries. With a charging speed of 4 amps per hour, a 12AH battery can be fully charged in just 3 hours. This 4-step charger automatically switches off when the maximum charge capacity is reached. This smart charger has the ability to keep the battery moving and in good condition. When the battery reaches 75%, the charger automatically switches to trickle charging to slowly charge the battery and maintain the voltage. This ensures a longer battery life. Product specifications: - Suitable for charging Bosch Li-Ion batteries - Charging speed: 4 amps per hour - Full charge time for a 12AH battery: 3 hours - Automatic switch-off at maximum charge capacity - Trickle charging at 75% battery capacity - Keeps the battery moving and in good condition.