WIDESHERE(TM) creates a large “sweet spot” for all listeners, even from the smallest speakers ; Aluminum dome tweeters deliver high output, extended frequency response & natural music reproduction; Butyl rubber surrounds provide durability & deeper mid-bass impact; Textured ABS gasket assures a rigid linear seal to the mounting surface; Pure copper voice coil creates a strong magnetic field with a very thin extrusion; Kapton voice coil former is lightweight & efficiently dissipates heat; Natural fiber allows flexibility while the infused epoxy gives strength during the manufacturing process; Over-coil cooling system allows air exchange over the voice coil through the spider; Heavy gauge progressive-die stamped steel frames for ultimate rigidity; 4″; 80W max/40W RMS; Freq resp: 55Hz-19kHz; Mounting dia: 3.69″; Outside dia: 5.39″; Mounting depth: 3″; Pair;