The OMNITRONIC PAS-181A MK4 is an active PA subwoofer for touring applications and permanent installations. Its vented 15 mm multi-layer plywood cabinet houses one 18-inch woofer with a 4-inch low-frequency voice coil and provides 700 W RMS power handling. The frequency range is 35 to 200 Hz, with a maximum SPL of 129 dB. Integrated DSP presets include FLAT, KICK, and DEEP, while XLR outputs provide switchable high-pass filtering. The cabinet has a black metal grille, two carrying handles, and optional wheels.