The Thunder5500 offers a variety of features including high power handling, rubber surround, tinsel leads woven in the spider mated to heavy duty chrome push terminals and attractive cosmetics. The voice coils are wound with 428 degree F aluminum, for an extremely reliable, high power handling subwoofer. These new subwoofers also feature MTX's proprietary Spider Plateau Venting technology, which ensures a cooler, more reliable subwoofer.