Built for real-world marine duty, this M6-10IB is designed to operate without a dedicated enclosure. Long excursion capability and rugged suspension systems combine to produce deep, powerful bass that will transform your boat´s audio system. With appropriate system setup, the addition of a subwoofer allows your smaller main speakers to be free of the burden of reproducing low frequencies. This allows your whole system to play louder and to sound cleaner at all listening levels. Built for real-world marine duty, this M6-10IB is designed to operate without a dedicated enclosure. Long excursion capability and rugged suspension systems combine to produce deep, powerful bass that will transform your boat´s audio system. For best audio performance, the M6-10IB is best used with amplifier power in the 75-250 W range and is optimized to operate with a large volume of air behind it (at least 1.5 cu. ft. / 42.5 l). All JL Audio marine speakers are saltwater-rated, utilizing corrosion and UV resistant materials throughout to deliver years of listening enjoyment. FEATURES: Saltwater-rated and built with corrosion and UV resistant materials throughout; Long-excursion woofer design with rugged suspension systems; Optimized to operate without an enclosure behind them (infinite baffle); Mounting Application: Infinite Baffle (at least 1.5 cu. ft. / 42.5 l of air volume behind); Continuous Power Handling: 250 Watts; Recommended Amp Power: 75 - 250 Watts; System Efficiency: 86.7 dB; Nominal Impedance: 4 ohms; Built in USA with Global Components