My wife has a Sony Ericsson phone that would not hold a pair with a Motorola headset. I figured, let's buy a Sony headset and it should have good compatibility. I was right! It works flawlessly. The sound quality is unmatched both for the person using it and for the person you are speaking to. The range is incredible and the battery life is unreal. The unit is very comfortable for all day use and the quality of construction is A-1. I'm sure that it works with other brands but if you have a Sony phone, this device is a must. I strongly recommend it.