Unit arrived without any record; obviously this is probably not necessary for a lamp but how to batteries: pulling on the rear panel? slidably? But in which direction, left or right because obviously there is no sense of the arrow indicated on the back of the lamp. In short, we lost time. Once installed, there are bad contacts, lighting is really boom and sensor detects what he wants and when he wants, but rarely you. This lamp is really very poor. Do not buy.