Functions:ch TFT LCD indoor monitor with or camera (max to 4monitors)2.4GHz digital frequency hopping and encryption technology, transmission distance up to 300 meters at open area, robust anti-interference;Hands-free call and talk function, Unlocked by olSuit for apartments, villas, hotels, offices, public buildings etcFeature:Clear night visionRain shield for the outdoor camera is available;16 chord melodies for option, melody volume is adjustable;Date (only one Outdoor Camera with one indoor monitor is available) and time appears on screen;Indoor monitor store up to 100PCS pictures, pictures mark date and time (500PCS picture optional if expanded-memory).Brightness and talking volume are adjustableMini USB charging interface, lithium battery is replaceable and rechargeable,