Previously ordered a rotating beast window cleaning robot. I was disappointed because it wasn't easy climbing and there were a lot of laps left. I was impressed by this Robert. It works fast, sucks very well and removes dirt very well. Just spray some Windex on the pad and just place it on the window. If you need more windows, spray directly on the window. Removes dirt much better than a rotator. Get in with no problems. Much less noise. I'll probably buy another one so I can get the job done faster