Rockville RBS15 Big Single 15" SPL Side Vented Car Sub Enclosure Box 4.5 Cu Ft Rockville RBS15 Big Single 15" Vented Subwoofer Enclosure Proudly Made In The USA, Using Only The Finest Quality Materials - For The Best Level of Performance From Your Subs! 3/4" USA Heavy Duty MDF Construction, Tuning Frequency: 37 Machine precision cut mounting holes. Top of the line Glue for extra durable adhesion Designed, tested, and engineered to work with most of todays popular woofers. These enclosures are built with the quality additives needed to maximize the performance of any sound system. Rockville RBS15 Big Single 15&#034; Vented Subwoofer Enclosure Proudly Made In The USA, Using Only The Finest Quality Materials - For The Best Level of Performance From Your Subs! 3/4&#034; USA Heavy Duty MDF Construction Machine precision cut mounting holes Top of the line Glue for extra durable adhesion Designed, tested, and engineered to work with most of todays popular woofers. These enclosures are built with the quality additives needed to maximize the performance of any sound system. Tuning Frequency: 37 Hz Type of Enclosure: Vented Enclosure Sub Size: Single 15&#034; Dimensions in Inches: 18&#034; L x 32&#034; W x 18 H&#034; Top and Bottom Depth: 18&#034; Mounting Depth: up to 15.5&#034; (enough depth for any sub on the market) Gross Volume Per Sub (Measurement for the outer dimensions of the box): 6.3 Cubic Feet Net Volume Per Sub (Measurement for the outer dimensions of the box less the thickness of the wood): 4.5 Cubic Feet