The ring will only available when use outdoor unit to call indoor unit.

Specification:

LCD :7 inch color LCD 
Dimensions of Monitors:235.5X165.5mm
Power Input:AC 100V-240V 50Hz/60Hz
Power Output:DC 15V
Current Output:1200MA
Call Duration Time:120 Seconds
Monitor Duration Time:40 Seconds
Maximum Transmitting Distance:30 Meters
Power Consumption:Static state<0.5w, Calling<10w
Camera Viewing Angle:62 Degrees
Working Temperature:-10 degrees Celsius~+50 degrees Celsius
Comparative Temperature:10%-90%(KH)

Features:

1. High definition camera, is adjustable in four directions: up, down, left and right for best view.
2. The door which need to be released can be unlocked from any indoor units.
3. 1-to-2 type.
4. Suitable for the villa with one door and two main rooms. Sounds from two indoor units will be heard and image will be presented on the video indoor units when someone presses the button of outdoor unit.
5. Hands-free intercommunication between indoor and outdoor units.
Waterproof aluminum alloy panel of outdoor unit.
6. Night vision.
7. 7-inch display is with high definition, low power consumption, no radiation.
8. Electric-controlled unlocking.
9. Monitoring the outdoors.
10. 8 different chord melodies available.
11. Adjustable chrome and brightness.
12. Adjustable volume of melodies and intercommunication.
13. Enclosed 15m cable and an adapter for DIY.
14. Slim fit designed aluminum alloyed indoor unit.

Item Includes:
1 x  Video Doorphone System
2 x Power Supply
1 x Connect Cable