This device works OK with my KRZR but you get what you pay for. Sometimes the sound is "crackly" and broken up. I need to have the volume all the way up most of the time.The volume buttons are also hard to find when I'm using it. It's hard to tell if I'm pushing the buttons or not. Since the headset fits so loosely I have to hold the device with my thumb while pushing the up volume button. The problem is that my thumb ends up pressing the down volume button at the same time. This causes the device to mute unintentionally.Same problem with the other button. It's used for all of the other functions. Since I can't really tell if I have pushed it I don't know if I have ended a call or just put it on hold. I always have to open the phone to check and make sure.It seems to add a lot of latency to the conversation, but that my be true with any BT headset.It fits loosely on my ear. If I turn my head fast enough if flies off. I don't mean whiplash fast either.I doubt that I would purchase another one of these.