The DS Four-Inch Coaxial Speakers are a perfect upgrade for great sound in your car doors. Using zero protrusion PEI tweeters ensures you get every bit of clarity you need, without interfering with factory grilles. A stamped steel framework supports a ribbed, UV-treated foam surround and rigid polypropylene cone with EVC (Extended Voice Coil) technology, for the best sonic quality. These DS speakers work best with 30 watts of recommended power.