Source Four LED S2 Lustr+ ERS Engine Body Only WhiteETC Source Four LED Series 2 luminaires feature the same size, look, optics and beam angles as a conventional Source Four fixture, with the efficiency and energy savings of an LED. They also use the same barrel, so you can easily retrofit your inventory. For the highest quality, controllable beam, Source Four LED Series 2 luminaires can accept any standard Source Four lens tubes, plus a special LED only 50 lens tube. You can achieve the best results