I bought it a long time ago from someone who came from Moscow. I used it a few times, but I’m not using it anymore since I don’t feel the need right now. However, it was helpful when I wore it. It’s a DAF device. SpeechEasy is more expensive, but it doesn’t have the FAF feature, and this one was cheaper than SpeechEasy. There’s also an app called DAF Pro, which I bought earlier — it’s affordable and I recommend it. A delay of 50–75 ms is usually suggested, but you need to experiment to see which delay works best for you.