Features 1、Real Time Two Way Voice: This wireless intercom doorbell offers real time two way voice, providing a secure and private conversation with anti interference features. It's great for both home and office use, ensuring you never miss a visitor or important delivery. 2、One Button Operating: With a simple one button design, this doorbell makes it easy to call, answer, and end conversations. After 1 minute of conversation, the call will automatically end, making it convenient and efficient for quick interactions. 3、Loud and Clear Alerts: The doorbell features a flashing light and ringtone alert that lasts for 20 seconds, ensuring you're aware of any visitors. With a ringtone volume of 108 decibels, it's louder than a typical smartphone ringtone, so you won't miss any calls. 4、Long Lasting and Convenient Power: The outdoor unit has a battery life of 6 months. The indoor unit plugs into a 5V1A power adapter, ensuring it never runs out of power. The installation is easy, with the outdoor unit simply sticking to the wall with adhesive. 5、Premium Design and Long Range: The buttons are made of a plastic and silicone structure, with a high gloss finish for a high end look and feel. The intercom has a tested range of 100 meters, making it suitable for buildings with up to 4 floors. Plus, the indoor units can call and communicate with each other, adding an extra layer of convenience. Specifications Specifications: Method: Full duplex intercom Power Supply Method: A rechargeable li battery for the outdoor unit, and a 5V1A power adapter for the indoor unit Working Temperature: -20 ° C to 55 ° C Transmission Distance: About 100 meters in open space, 5-20 meters in partition walls, floors 1-4 Working Frequency: 433MHz Working Hours: The outdoor unit is recharged once, and the working time is about 6 months External Battery Capacity: 1000mAh Charging Time: Approximately 3 hours when the external unit is fully charged Music Ringtones: 5 ringtones Product Size: 68 * 70 * 27mm/2.7 * 2.8 * 1.1inch Package List 1 * Outdoor Machine 1 * Indoor Machine 1 * Instructions 1 * Screwdriver 1 * USB Data Cable