Fits Round Mounting Tube Sizes 1-5/8", 1-3/4", 1-7/8", 2", 2-1/4", 2-3/8", 2-1/2" | Each enclosure holds two 6-½" Marine Speakers | Weather-proof empty enclosures with slotted mounting holes to accommodate different bolt patterns | Nine-degree axis rotation | Compatible with all KICKER 6-1/2-inch component speakers, coaxials and horns