Top features: - HD video streaming during both day and night - Two-way communication to interact with your visitors - Quiet time to keep things peaceful in your home - Compatible with Google Home devices and Amazon Alexa HD video streaming Check who's at your door at any time using the Nest Hello Video Doorbell . Capable of 24/7 streaming, it sends an alert to your smart devices when someone presses the doorbell, including a picture of what happened. The smart doorbell is also capable of detecting people, motion and sound, so you can always be aware when somebody is outside your door. Using HDR and night vision, the Hello delivers bright, crisp images to your smartphone regardless of the time of day. Using the Nest app, you can see whoever is at your door from head to toe, whether it's a family member or a parcel left on the doorstep. If you own Google Home devices, you can even receive visitor announcements when there's somebody at the door. Two-way communication You can communicate easily with anybody at your door from wherever you are. Two-way communication makes it possible to have a conversation, or you can simply choose from a list of quick responses in the app to play a pre-recorded message to the visitor. Quiet time If you have a sleeping baby or pets who get easily startled, you might not want to have a doorbell disturbing the peace and quiet in your home. You can turn off the chime from your Nest app, whilst still receiving notifications on your smartphone so that you never miss a visitor. Compatible with Google Home devices and Amazon Alexa In addition to being compatible with Google Home devices, the Hello is also compatible with Amazon Alexa. This makes it easy to create your ideal smart home setup to live an easier lifestyle. Please note: professional installation required. Requires a 12 ¿ 24 V transformer. Operating temperature is -15 - 40ºC.