Engineered as the reference standard for marine subwoofer performance, the M7-12IB is capable of producing staggering amounts of jaw dropping bass in infinite baffle applications. Built to withstand real world marine duty, this M7-12IB is designed to operate without a dedicated enclosure. It boasts a monstrous 4 in voice coil and rugged suspension system to deliver outstanding linear excursion for high output and power handling. M7-12IB is best used with amplifier power in the 200 to 600 W range and is optimized to operate with a large volume of air behind it (at least 3 cu-ft/84.95 L). Like all JL Audio marine speakers, this driver is built to withstand a real salt water marine environment and deliver years of listening enjoyment.