The Yale Smart Video Doorbell lets you see, hear and speak to visitors from anywhere, anytime. Offering a crisp 1080p HD image, a 154° field of view, two-way audio talk, live viewing, and 6m night vision for clear footage that can be viewed 24/7 in the Yale Home app, the Yale Doorbell is easy to set up and use.  For ultimate ease, you can choose to have your Doorbell powered either via the built-in rechargeable battery (battery life 4-6 months depending on usage) or hard-wired into the mains.