Signal Construct Ultra Bright LED Recessed Panel Indicator E5.5 15-18V AC – Signal Construct MEDE5513, This ultra bright yellow LED panel indicator comes in a screw mounting E5.5 case that has a recessed internal reflector. Operating voltage is 15 to 18V AC and the viewing angle is 50°. Signal Construct MEDE5513 5.8mm Yellow LED Indicator 15-18VAC Lamp E5.5