Easy Installation Additional Installation work is not needed because the 2-wire cable
and box of existing door phone can be used. Free Voltage A specially designed transformer allows you to use under any
voltage condition from AC 110-250V. Compact Infrared LED As the infrared LED is compactly designed, it can be used at night,
or in dark places without any extra lighting. Extensions (Additional Monitors): Up to 2 monitors with 1 camera is possible. Easy Monitoring Watching and communicating with outdoor visitor over handset. Door release Can be combined with electric lock (optional).