Used this for past 10 days and people are complaining about my voice - I stick my palm one 650 on my belt -Other end can not hear me properly when I'm using this head set. Works well where no air blowing around - something like in the house or in your car. You can not use on the bus as you need to talk low - other end can not hear you..Just be careful where you use it - Start feeling heavy in about 15 mins on the ear...(so I change from right to left ear or vice versa...)