Bests & Worsts Reviews from Amazon

I'm taking one star off because the description for this product is fairly poor and does not make clear exactly what kind of connection it is meant to create. The product itself is high-quality and works perfectly once you figure out how to use it. I purchased this reducer to connect my 2.5" shop-vac hose to my Ridgid table saw, which has (what I believe to be) a standard 4" dust collection port. Initially, I expected that the 4" side would fit inside or around my saw's DC port, and the 2.5" side would fit inside or around my shop-vac hose. However, the 4" side was the same diameter as my DC port (i.e. they were both "male" pieces requiring a "female" connector to make a male-to-male bridge). Accordingly, I realized that this reducer is meant to fit inside a standard 4" DC hose, not a DC port on a tool. So, I cut a few feet of DC hose, connected that to my table saw's DC port, and then fit this reducer into the hose. I then connected my shop-vac hose to the 2.5" side of the reducer with no problems. Hopefully this clarifies what I had some difficulty discerning from the other reviews: this product appears to be designed to connect a 4" hose to a 2.5" hose; not to connect a 2.5" hose directly to a 4" DC port. Of course, it is possible that other tools do have a DC port that this will fit inside or around, but if you order this part and are unable to make a direct shop-vac-to-tool connection, try using a short length of 4" hose as a bridge.