Although the car environment is harsh it s downright cozy compared to what your boat has to deal with, Despite all the moisture vibration and corrosion it has to play loud, Just because you re on the water doesn t mean you have to go without bass, Put the M110S4 in your boat and you just may redefine party barge ! This subwoofer is designed for free air/infinite baffle applications, SKU: TBAL2235