The WV 2 and the KV 4 are the optimum team for clean windows and other smooth surfaces. With the vibrating battery-operated wiper KV 4, dirty surfaces are effortlessly cleaned in the first step. In the next step, the remaining moisture is comfortably extracted with the Window Vac 2. The KV 4's automatic water supply and vibration function quickly loosens dirt without scrubbing. The Window Vac's electric water extraction guarantees a drip-free and streak-free clean result. Kärcher's new duo is easy to handle, clean to use and saves a lot of time and effort.