By buffer function we mean the electronic control of the charging current, automatic interruption and reset (it allows you to keep the battery of your car / scooter or motorcycle charged when you are not using the vehicle.Battery interrupts the charging process, when the battery is fully charged and automatically starts charging again when the total charge of the battery decreases). Suitable for hermetic (GEL) and electrolyte-free (WET) batteries with 12 volts of motor vehicles, cars and vans.