1. Lithium battery powered, energy-saving and more environmentally friendly; 2. Millions of high-definition pixels, with infrared night vision function, it is still clearly visible even in the dark; 3. PIR human body sensing, when the presence of human body is detected, it will take a photo and push it to the mobile phone; 4. The built-in microphone can support two-way intercom function; 5. Can be remotely awakened, PIR awakened, button awakened, and pushed to the mobile phone App at a very fast speed; Active : remote , PIR , device button Support high-definition video recording, video playback, etc. Working temperature: -10℃-55℃ Working humidity: 10%-90%RH Resolution: 1920x1080 Voice system: two-way voice intercom Viewing angle: 166° Night vision light: 6 850nm infrared lights Storage function: SD card 16G/32G/64G/128G/cloud storage [supports up to 128G memory card, memory card is not included in the shipment, and the memory card needs to be prepared by the buyer] Note: Without 2 18650 batteries Colour:Black Material:plastic Package Contents: 1 x doorbell 1 x USB cable 1 x English instruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.