<p>An injection mounded flush-mounted electrical plastic box for electrical elements having a hollow lug on at least one side wall. Such hollow lug has an insert with a hole with internal threads with limited displacement inside the hollow lug such that the hole remains accessible. Also provided integrally moulded is at least one knock-out on at least one of the side walls and the back wall and at least one detachable connector pin that can be snap fitted inside a through hole provided on at least one of the side walls.</p>
