ECOVACS WINBOT W930 Automatic Window Cleaning Robot 4-stage cleaning for maximum efficiency. 1. The Cleaning Pad sprayed with WINBOT Cleaning Solution moistens, loosens and absorbs dirt. 2. The Squeegee clears dirt from the window. 3. The Squeegee swipes again to remove remaining waterborne dirt. 4. The Cleaning Pad wipes the window to a dry, spotless shine. Fast & thorough cleaning with Smart Drive Technology Cleans framed and unframed glass of any thickness - including Thermopane Pathfinder navigation calculates a custom cleaning path for speed and efficiency, while intelligently avoiding edges and obstacles An Eco-friendly, green machine you can feel good about using