Ive been told by a fellow member here that these Microwave ones are definately worth the cost: http://nl.aliexpress.com/item/FRee-...Microwave-Motion-Sensor-M001/32521612199.html
I believe they fit inside a standard electrical box.. and work even with a blank cover installed on it.
I believe they fit inside a standard electrical box.. and work even with a blank cover installed on it.