Ultra-high power handling capacity guarantees long-term durability 4" diameter copper voice coil on fiberglass former, 4 ohm impedance Weather-resistant paper cone and dust cap, treated cloth edge.Die cast basket is light yet strong, ready to handle rough travel Massive, optimized motor structure helps move serious volumes of air Capable of sustaining thunderous levels of sub-bass Hand built in the USA.Power Handling (RMS) 1200 Watts Power Handling (max) 2,400 Watts Impedance 4 ohms Frequency Response 36 to 820 Hz Eminence IMPERO 18C 18" High Power Driver Speaker 4 Ohm 1200W The Eminence Impero 18C 18" high power pro audio speaker is optimized for use in vented enclosures. Its 1,200 watt continuous power rating is a result of Eminence's extensive experience designing and manufacturing loudspeaker drivers for serious professional use. This 18" cast frame transducer features a 4" diameter copper voice coil that is wound on a fiberglass former. A large magnet, extended and vented pole piece, bumped back plate, and 1/2" thick x 7-1/2" diameter top plate ensure substantial motor strength, resulting in tremendous bass output. The Impero 18C's performance is Ideal For 4 ohm full-range 3-way boxes, bass guitar boxes, and compact to medium-sized subwoofer speaker systems. Recommended enclosure volume: Vented: 113.2 ~ 277.5 liters / 4 ~ 9.8 cu. ft.