Mississippi Code
Article 15 - Starting and Turning; Signaling
§ 63-3-709. Manner of signalling generally

The signals required in this article shall be given either by means of the hand and arm or by a signal lamp or signal device of a type approved by the department. When a vehicle is so constructed or loaded that a hand and arm signal would not be visible both to the front and rear of such vehicle, then said signals must be given by such a lamp or device.