Abstract: An adjustable neck is provided for adjusting a lamp, in particular a lamp plugged onto a low-voltage rail, in as many alternative directions as possible. The adjustable neck is mounted between a clamping socket of the lamp and the replaceable incandescent body or bulb. The adjustable neck includes several joint members, each consisting of a ball portion that can be plugged into a corresponding joint seat portion of a next adjacent joint member and held there by a friction fit. The incendescent body can be surrounded by a lamp shade provided with ventilating slots. The clamping socket is embodied such that a positive anchoring is achievable even in the case of larger, heavier lamps.