These flared ports virtually eliminate port noise for your custom subwoofer box. They are available in 3-inch, 4-inch, and 6-inch diameters. The flared port tubes can be cut to create anywhere from a 5" long port to a 17" long port (4" to 16" effective port length).
Please be sure to add 1" to your calculated port length to determine the correct flared port length.
Please ensure that you have at least 1/2 of the port diameter between the inside end of the port and the box wall.
The outside flare of the 3" port is 6.25" in diameter and the outside flare of the 4" port is 7.25" in diameter.