With the Kärcher FC 4-4 Battery Set 4B-Duo, you can adjust the cleaning position to your floor type and the amount of dirt. For instance, you can increase the speed and water volume for stubborn dirt. Since the electric mop absorbs both dry and wet dirt, there's no need to vacuum before mopping, allowing you to clean faster. The dual water reservoir separates clean and dirty water, ensuring you always use a fresh mop brush. Water consumption is coordinated so that your wastewater tank is only full when the cleaning water tank is empty, preventing unnecessary interruptions in your cleaning task. After use, you can clean the mop brush in the washing machine. With a full battery, you can clean an area of 90 square meters. The cleaning water reservoir has a capacity of 400 milliliters, while the wastewater tank holds 200 milliliters.