4PCS Woofer Speaker Inverter Tube with Opening 42.5mm Length 80mm Suitable for 4-6 inches

Feature: 1. Speaker inverting holes, also called sound tubes and air holes, are often used in inverted speakers. 2. The main reason is that the sound pressure of the airflow vibrating in the box is poured out to overlap the sound pressure radiated in front of the speaker to produce a bass effect. 3. Its inner wall is smooth and the ends are flared. Made of high quality ABS plastic, it is sturdy and durable. 4. The airflow is very smooth and the airflow is obviously improved. It is suitable for 4-6 inch speaker. 5. Compact and lightweight, it is easy to carry and easy to install. Specification: Item Type: Inverted Tube Total Length: Approx. 80mm3.15in (as picture) Speaker Housing Opening Diameter: Approx. 42.5mm1.67in (as picture) Package List: 4 x Inverted Tube