Dual 18-inch vented subwoofer is designed with a small front surface area for installation against walls and under stages with minimal sightline issues. Each subwoofer has integral rigging points and also ships with (4) rubber feet that can be placed anywhere on the cabinet, placing the subwoofer on the ground on any of the available five sides. The 18-inch drivers used in the 218-I have a Neo magnet structure for light weight and a high-temperature voice coil with a large Xmech rating for reliable operation.