86mm x 91mm Speaker Port Tube Subwoofer Bass Reflex Tube Bass Woofer Box 4pcs U-Joints 5 accuracy and fine-tuning function

5 accuracy and fine-tuning function

Package Content: 5pcs of EACH: Hex Bolts

with low frictional resistance

Suitable for the 5mm - 9mm thick glass

Metal material stands up to outdoor use or indoor use whatever dry or wet

86mm x 91mm Speaker Port Tube Subwoofer Bass Reflex Tube Bass Woofer Box 4pcs U-Joints 5 accuracy and fine-tuning functionFeatures: Speaker Port Tube is used to improve the bass response of many types of speakers. There are plenty of types to help you with your vented box design, and carries tubes of every shape and size, including adjustable length ports and flared ports. These port tubes are a reliable, convenient installation, while at the same time providing a finished, "pro" look to your bass reflex speaker building project. Normal tubes suffer from nasty turbulence