The IC 4 PRO model is part of the WORK Pro IC PRO Series which consists of three ceiling speakers with woofer and tweeter. This series is made of impact-resistant ABS plastic and has a metal grill next to a rear metal enclosure, where the crossover network and the transformer are. The bass reflex design, along with the internal volume of its cabinet and resonance tube, provide great performance in low frequencies. They are suitable for installations with high impedance voltage lines (70V, 100V) and low impedance (8 ohm). The power selector is accessible from the front of the loudspeaker and has a removable Euroblock connector, contained in a metal compartment.