The Dayton Audio Classic Series subwoofers offer solid value at lower price points. No compromises were made in the design, materials, or construction of these rugged 4-ohm powerhouses. The drivers feature a vented pole piece with copper cap, bumped back plate for improved excursion capability, Kevlar reinforced cone with rubber half-roll surround, and a high-temperature 4-layer copper voice coil wound on a polyimide former.