43mm length tube is compatibleable compatible 2-4in compact speaker.93mm length tube is compatibleable compatible 5-6.5in compact speaker.105mm length tube is compatibleable compatible 8in compact speaker.123mm length tube is compatibleable compatible 8in compact speaker.Made of high quality ABS plastic, this product is sturdy and durable.The speaker port, also known as the sound tube and the air hole, is often used in the ported speaker.It mainly suppresses the airflow sound of the speaker in the box and overlaps the sound pressure radiated in front of the speaker to produce a bass effect. Specifications:Material:ABSColor:BlackLength:43mm/1.7in,93mm/3.66in,105mm/4.13in,123mm/4.84in,(Optional) Note:Please allow 1-2cm errors due to manual measurement,pls make sure that you do not mind becompatiblee you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package Includes:2x Speaker Inverter Tubes