【Amazon Device】Ring Video Doorbell 4 | Answer from anywhere, smartphone compatible, intercom, door phone New, unused, unopened List price: 23,980 yen Please contact the manufacturer directly for initial defects or missing contents as the product is unopened. 【No power installation required】 Wireless design that does not require power installation due to the use of a detachable rechargeable quick-release battery. It can be installed near the front door or in the location of an existing door phone (recommended about 6M from the router or access point) as long as the Wi-Fi signal reaches. Japanese products come with a no-drilling mounting base. You can also consider it for places without an intercom with a TV monitor. 【Detects human movement】 Equipped with a function to detect motion with infrared and camera sensors and notify the Ring app. You can customize the settings in the Ring app to detect necessary events, and you can also use the privacy mask function to hide areas you don't want to be captured by the camera. 【Rewind 4 seconds】 The color Pre-Roll video preview, which records the scene up to 4 seconds before motion detection, allows you to grasp the beginning to the end of the event. 【You can see the video and make calls even when you are away】 Equipped with 1080p HD video live video and two-way calling function, you can check the situation at the front door in real time with your smartphone with the Ring app installed. You can talk to visitors even when you are away. 【Like an intercom with a monitor】 If you enable the Alexa skill, you can check the video and make calls on your Echo devices with screens and Fire TV series.