The V Tech DM221 Audio Baby monitor has a 1000ft range and gives off a vibrating sound alert should your baby make a noise. It produces crystal clear transmission, meaning you do not get crackling in the background. It has a 5 bar sound light which indicates how loud the sounds are in your baby's room without you having to listen to them. There is also a two way talk back which means you can soothe them from another room. The rechargeable battery means that you can walk around for 18 hours without recharging. There is also a belt clip which will allow you to walk around hands free.