Function Operation: 1. Power On/Off: When you press the "power key", the inner part will light up, keep pressing the "power key" for 3 seconds, the device will turn off. 2. Review Photo: In power on mode, press "left key" or "right key" to review photos. 3. Delete All Photos: In power on mode or when reviewing photos, press "left key" for three seconds to delete all photos in memory. 4. Delete Single Photo: When reviewing photos, press "right key" for three seconds to delete one photo in memory. 5. Set Power Off Time: In power on mode, press "right key" for three seconds to select power off time: 15s/25s/off. Specification:● Condition: 100% Brand New● Item Type: Smart Door Viewer● Material: ABS Plastic● Screen Size: Approx. 2.4 inch● Screen Resolution: 320 x 240● Sensor: 0.3MP CMOS Active Digital Image Sensor● Viewing Angle: 90°● Motion Detection: Not Supported● Taking Pictures: Support● Power Supply: 600mAh● Doorbell Function: Not Supported● Storage Method: Memory Card Storage● Night