Lanzar DCTOA18D Distinct Open Air DVC Distinct Series 18-Inch High Power IB Open Free-Air 4 Ohm Subwoofer DVC, Set of 1 Lanzar's Distinct Series (DCTOA) Open Free-Air Subwoofers provide you with the audio performance you need without requiring heavy and bulky speaker boxes. Engineered to create clean and distortion-free audio reproduction, these Open-Free Air woofers utilize your vehicle's tight spaces to create an IB (Infinite Baffle) application. Forward firing projection and minimum air-space requirements make these speakers ideal for mounting in tight spaces like trunks, under seats and side panels. Enjoy high-power output, clean 'unboxed' sound and impressive low frequency bass reproduction when you keep your woofers fully exposed. Upgrade your system with no enclosure or concealment necessary. Lanzar's Distinct Series (DCTOA) Open Free-Air Subwoofers will add versatility that are perfect for custom applications and installations. Available in single and dual voice coil styles.