STATE OF THE ART: PH.10 was designed and engineered in the USA; these subwoofers give you that sense of nostalgia throwback Flat Piston subwoofer look you remember with all the goodie goodies of today's available technology for big output potential. Newer technology with the finest materials to consistently deliver you the best performance, sound quality, reliability, and value in the car audio industry. Phantom Series Subwoofers use fiberglass stranding woven together for ultimate strength and minimal elasticity. A heavy soaking in epoxy combined with the sonic qualities of pulp paper backing creates a premium feel.