1. Color CCD/CMOS camera, 4''/5.6'' (main monitor), 2.5'' (monitor) color TFT display;
2. 30s sixteen-chord melody ring, 15s monitor if needed, 120s confidential conversation;
3. 3 kinds of ring available, 3-level volume adjustable,
4. Hand-free monitor, inner-call via broadcasting, intercom function;
5. Rainproof door station panel, camera lens angle adjustable, flush-mount for door station;
6. Four wires polar connection among door station, main monitor and monitor, trigger signal to unlock, which is workable with various locks;
7. Power supplier: built-in power for main monitor, adapter plug-in for monitor;
8. No dual conversation between door station and monitor.