This subwoofer port tube is designed for bass reflex tuning within car audio enclosures. Made from black plastic, the cylindrical tube features a 100mm diameter to help manage airflow and optimize low-frequency response. Its design includes a flared lip, which allows you to mount it securely into the enclosure wall while reducing turbulence. It is a practical choice for anyone building or modifying a custom subwoofer box to achieve a specific sound profile.