Baby Monitor
I purchased a a baby monitor so that I would be able to hear Diana when I was upstairs. I just wanted to be certain that I could hear her if she needed anything.
This has worked very well. The range is great and the volume output is excellent. The set that we have came with adapters to plug them into a wall outlet so I leave them on all the time. We have had them for about seventeen months now and they are still working great.