Durable Material Construction: Made from sturdy and lightweight ABS plastic that ensures long-lasting performance and easy installation Baffle Cutout Diameter Specification: Features a baffle cutout diameter of 82mm for precise fitting and secure mounting Precise Dimensions: Measures 91mm mouth outer hole diameter x 110mm length, with mouth inner hole diameter of 58mm for optimal sound projection Bottom Diameter Measurement: Bottom outer hole diameter measures 72mm Enhanced Bass Response: Increases the bass response of your audio system and is recommended for use with 6.5-8 inch speakers Versatile Application: Suitable for car DJ speakers, subwoofers, hifi home theater systems, and professional audio woofer setups Complete Package: Includes 2 pieces of speaker bass tube accessories reflex ports for your audio enhancement needs Material：ABS plastic Baffle cutout diameter：82mm Size ：Ф91mm（Mouth outer hole diameter）x110mm (long) ,Mouth inner hole diameter:58mm Bottom outer hole diameter:72mm ABS plastic is sturdy and lightweight.The Bass Tube can Increase the bass response of your system,Recommend for 6.5-8 inch speaker.