The 118.HSB is a high-output 18" subwoofer system housed in a strong molded enclosure that's impervious to weather, temperature extremes and moisture. Thanks to its unique enclosure design and powerful One Systems 18" woofer equipped with a 4" voice coil, the 118.HSB delivers extended low frequency response and high impact bass from a compact enclosure. The 118.HSB provides the full complement of One Systems’ weatherproofing features including 316 marine-grade stainless steel suspension hardware and enclosure reinforcements plus a HYBRID stainless steel grille with marine capable coating. The 118.HSB also offers an array of optional marine-grade stainless steel suspension hardware including eyebolt rigging, U-Bracket, Pan / Tilt bracket and Pole Mount brackets for placement and aiming flexibility. Add solid, high-impact low end response to your system by including the 118.HSB.