HEAVY-DUTY CONSTRUCTION: The durable 5/8-inch wood construction is designed to reduce vibration, which can affect the performance of the subwoofers. Additionally, a special bonding sealer is used to create an air-tight seal to increase joint strength. The 3/8 inch Plexiglas window is strategically angled for added support, giving full view of the reverse-mounted Flame Basket subwoofers. The black carpeted covering, internal LED illumination and Audiobahn logo embroidery give the enclosure an aggressive, custom look.