The M770-CCW component woofer is optimized to operate with a large volume of air behind it (at least 2 cu. ft. / 57 l). If you need a 7.7-inch component woofer that operates in a small sealed enclosure, select our M770-TCW, instead. Although M770-CCW component woofers can be used with as little as 40 W per channel, for best audio performance we recommend amplifiers capable of between 75-150 W of continuous power per channel. Please note: this listing is for a single component woofer with an attached 2-way, passive crossover network and a grille. No tweeter is included. Sold individually.