This is the xmartO add-on camera with 2K 3MP 1296p HD resolution and built-in microphone. It works as an add-on camera to xmartO expandable camera systems, or to an xmartO NVR. Please mind, IT DOES NOT WORK AS A STANDALONE CAMERA.It requires 5MP XMARTO NVR to work. If your NVR is 960p or 1080p, these cameras will have too high resolution. 3MP HD - the 2k (2304*1296) HD camera delivers crystal clear image with sound.