The invention relates to a module of electrical equipment (30) to be inserted into an electrical box (50), comprising: a case (31) made from an insulating material and defining an inner space for receiving an electrical mechanism (32); and at lest one snap-fitting means (40) for securing the case in the electrical box, comprising an attachment part (42) designed to attach to the electrical box, a tab that bears the attachment part and is flexible between a rest position and a deformed position, and means (43) for manoeuvring the tab in order to move same into the deformed position. According to the invention, the module also comprises retaining means that are designed to retain the tab in the deformed position.