Pioneer designed the TS-A4103 2-way speakers as a high-quality replacement for the 4"x10" factory speakers found in many General Motors and Saab vehicles. The crisp, full sound results from the union of an IMPP (Injection Molded Polypropylene) woofer and a 1-5/8" paper cone tweeter. Grilles not included. (Factory grilles are appropriate for most installations.). The woofer cones are constructed from injection-molded polypropylene. Thisprocess of cone molding assures a uniform cone thickness for superior linearity and clarity. In addition, the cones are lightweight and rigid for decreased distortion and superior bass response. Each woofer uses a treated cloth surround.