this is a unique product, it has a lcd screen and a swivel mount.  works great.  so great i got one for my wife. very clear, easy pairing.  yes it does not have an ac adapter but i bought a universal ac adapter for $10 at a discount store so i can recharge it at home.  to set up you have to charge for 2hours.  well that's hard to do in the car, so get an ac adapter since my wife and i have the same product all i need is one adapter.  any other time i could charge from the nice cig lighter adapter (has an on off switch).  so this is soooo nice i showed it to my partners and they want one.  cost a lot less than my "bug in ear" plantronics,  i've used the in ear units for driving,....this is way better. it can pair with i think 7 units.  i really like the lcd screen because you don't have to hear, remember beep sequences. the only reason i gave it a 4 for performance is the lack of a ac adapter.....you can't go wrong with this. now i hope this last a bunch of time.  also the swivel adapter allows you to mount in front or behind the visor and gives easy viewing....did i say i liked this.