A lot smaller than i imagined but then thinking about it this needs to be very small and very lightweight as it is to stay on the walls/ceiling etc. Have had cheaper ones of these before and they havent stayed good enough on the walls and floors to be used effectively but this does IT DOESNT FALL, its great very lightweight, very robust, excellent price only downside is how noisy it is because of the motor needed to suction it to surfaces and it will only work on smooth surfaces even on the floor any sort of carpeting is a no go.