Keep An Eye On Your Home With The Ring Video Doorbell 3 With Pre-Roll Technology. Our premium battery-powered doorbell with advanced security features including improved motion detection, an added near motion zone and Pre-Roll technology. With an additional 4-second video preview of each motion event, you’ll automatically start recording before you even receive an alert. Our premium battery-powered doorbell with 4-second Pre-Roll video previews. 1. 1080p HD video doorbell with enhanced features that lets you see, hear, and speak to anyone from your phone, table, or PC. 2. An upgrade from the original Ring Video Doorbell 2, enjoy improved motion detection and dual-band (2.4 of 50 GHz) wifi connectivity. 3. A step up from Video Doorbell 3, get 4 extra seconds of black and white video to show you what happened before motion was triggere with Pre-Roll. 4. Receive mobile notifications when anyone presses your doorbell or triggers your built-in motion sensors. 5. Easily setup by connecting your Ring Video Doorbell 3 to wifi through the Ring app and mounting with the included tools. 6. Record all your videos, review what you missed for up to 60 days, and share videos and photos . 7. Pair with select Alexa-enabled devices to enable announcements and two-way talk for convenient in-home monitoring. Runs on a rechargeable Quick-Release Battery Pack (included). Can be hardwired to an existing doorbell system or transformer for continuous charging (8-24 VAC, 40VA max, 50/60Hz). No halogen or garden-lighting transformers; no DC transformer/power supply. Estimated Install Time: approx 5 minutes. * Depth: 28 MM * Height: 128 MM * Width: 62 MM