Atrend's S12 Subwoofer Spacer ring adds .75 inches to most 12" subboxes to decrease the mounting depth of your subwoofer. Our S12s are versatile and easy to use in different applications. Bbox enclosures and accessories are built by the world’s leading manufacturer of speaker enclosures. A globally recognized brand that specializes in ensuring sound quality is delivered in each and every hand-made enclosure. Only trust Atrend for your subwoofer enclosure and car audio needs. CNC Machined to ensure accurate and consistent fit High Grade 3/4” MDF for a solid height adjustment and leak proof seal. Plush OEM Grade Charcoal Carpeting is durable and matches OEM colors. MDF Spacer Works with any 12 in subwoofer and or speaker. 12" speaker woofer spacer