I own two Plantronic M175 headsets. They work on both my Vtech Cordless phone and my older model Motorola cell phone. I like the volume control, mute button, and adjustable microphone level. I have only used it in the &quot;headset&quot; mode, and it is very comfortable. And finally, Plantronics customer support is the best. Even though I have had to replace my headset (perhaps due to my own neglect), they have been very prompt with sending me a replacement at no charge.