I bought this A/C unit for my bedroom--11x15, located on the 3rd floor of a rowhome. My windows are very small, so I was concerned about finding a unit that would fit in a smaller than normal frame. This model did the trick; it fits great in my 11" window, and cools the room quickly (I have the 5000 BTU model). The fan vent grill started making a vibrating noise about a month ago, but I was able to fix it by sliding a small piece of rubber against the frame of the grill to prevent the rattling. Seems to be a problem with the design of the vent...it can only be tilted up a small amount, and so it is prone to rattling. However, I love the unit, and would recommend it to anyone looking for a small but effective window unit!