Parts Express Speaker Cabinet Port Tube 3-3/4" ID x 7-5/8" Length Flared Bass Reflex Port for DIY Subwoofer & Speaker Box - Perfect for Home Theater & Car Audio Systems

The plastic was a little cheap and there was still some casting burrs in the threads and other areas of the port that I was sent. This is far from making it a bad product, but the time spent cleaning the threads up and making the plastic smooth is what caused me to rate this 3 instead of 5 stars.I may have been sent one that sneaked past quality control, and the plastic burrs were on the threads and the sides that would be in the speaker box, so they would not affect anything you would see.Otherwise, the port has plenty of ways to cut or customize it to perfectly fit your project, and since the plastic seems of good quality and the parts of the port that can be seen were of a very nice finish, if I didn't have to do any extra work to it, I would have given this product a 5 star rating.