Audiopipe Tubo12 Nippon 12 Subwoofer Cylinder Box

21Inch Long X 16Inch Diameter, (Which Includes The Turbo Vent On One Side Of The Tube). The Woofer Opening Is For A 12Inch Woofer. Air Space = 1.37 Cu. Ft. The Port That Runs Along The Top Of The Tube Is Square Along The Top Rather Than Round.