... : 7inch color TFT video door phone 2: unlock by ID card,by password,by key 3: handfree,night vision 4: ultrathin ... , Model:SMTV7E-DFunction and Features**plastic camera, unlock by ID card,by password,by key, good design,CMOS or CCD sensor ... .. **Brightness, chroma and ring adjustable. **3-chord melody rings for option.**two cameras can connected with four monitors.(different choice)**four ...