I had problems with this extension at first. I've tried connecting a few different USB-C USB 3.1/3.2 hubs to this extension without much success. I contacted the seller and reported my problem and they immediately apologized and offered to refund my purchase price (rather than asking for the cables to be returned). Looking through the product description, I noticed a message about reversing the connection when using USB 2.0 devices. Since I was connecting USB 3.1/3.2 devices, I didn't think it would apply to me. BUT. simply switching the connection to my USB 3.1/3.2 hubs solved the problem! I reported this later discovery to the seller and they still refunded my purchase price even though I found a way to get the cables to work. It goes beyond the call. I will not hesitate to purchase more products from this company in the future. Thanks for the great customer service!