xmartO 1080p HD Wireless Security Camera System 4 Channel NVR with 1TB HDD and 4X 1080p Full HD 2.0MP Wireless Outdoor IP Cameras, Auto-Pair, NVR with Built-in WiFi Router, WiFi Relay, Audio Support 1080p Full HD Videos - The 1080p (1920 x 1080) IP WiFi security cameras deliver stunning 2 million-pixel crystal clear videos, both day and night. All cameras are equipped with infrared night vision, which allows you to see up to 80ft in pure darkness. Audio Compatible - Each camera comes with audio port, which allows you add external microphone to hear and record voice, without extra power cable needed; the NVR outputs voice through HDMI & 3.5mm audio port. Of course, you can hear from the app as well. Professional WiFi Router Inside  This wireless security system is completed, standalone WiFi security camera system, with its own router built-in. This ensures its standalone, completed, specially-made long range wifi distance and hassle-free to your home network. Strong Long Range WiFi Distance - With built-in WiFi router and two external Wi-Fi antennas, this NVR forms its own strong and stable WiFi to cameras with distance up to 1000ft on open ground, and 200ft with obstacle. Take advantage of Dream Liner WiFi relay tech, you get even better wifi range. Auto-Pair, True Plug & Play  This wireless security system auto connects when turned on, as soon as you connect them to power and hook up to a screen, they will AUTO-PAIR and give you quad-view of 4 cameras immediately. This is really hassle-free plug & play. Wired cameras are doomed to be mounted only 60-100ft away from the DVR. The 12V low-voltage power cannot avoid power &amp; signal loss when coaxial/ Cat5 cables are longer than that. Running 4 or more long cables from different cameras to one single DVR is not only expensive, but also destructive to the place. The maximum line-of-sight range of 300 feet isreduced by each wall, ceiling, or other majorobstruction between the camera and base station. Battery cameras are not full-time security cameras. They work only when there are activities within 20ft or so. Battery changing is another concern especially when users are away from home. On open ground, you get about 1000ft mounting range immediately while plugged in. With xmartO Dream Liner WiFi Relay technology inside, you can set closer cameras as Wi-Fi repeaters to boost the WiFi range to 2 - 3 times that far. Likewise, the WiFi range is reduced by each wall, ceiling, or other major obstruction between the camera and NVR base. Featuring Auto-Pair technology, you only need to plug camera system to power and the NVR to a TV/ monitor. They will start to show and record videos. Unlike some multiple-camera systems, the xmartO cameras do not connect to your home WiFi. They connect to the built-in WiFi to avoid messing up your network. The NVR then join your home network as an Internet device, like a desktop PC. With the stand-alone WiFi router, the camera system works even if there is no existed network. Download and install App Scan the QR code on screen, or input the Cloud ID The 1080p (1920 x 1080) WiFi security cameras deliver stunning 2 million-pixel crystal clear videos, both day and night. With audio jack on the tail of each camera, you can add microphones to get audio embedded to videos. The NVR base has both HDMI &amp; 3.5&#034; audio ports to output audio to TVs or speakers. Audio can be played along with videos on mobiles. Please note that you need to go to System setting - CH setting - Encode setting, change Encode mode to &#039;AV Stream&#039; to get audio from camera after adding external microphone. Cameras are well-built with IP66 rating and proper-sized. Designed to be mounted anywhere indoor or out. With 3 professional LEDs array in each camera, it sees up to 80ft away in pure darkness. To help you staying alert of your place, especially when you are away, App pushes notifications to your mobile, or send you emails with snapshots when activities detected. With 1TB hard disk in, the NVR records past around 30 days of all 4 cameras 24x7. With support of maximum 6TB HDD, the system holds up to past 180 days. The record can be accessed, clipped and shared from anywhere anytime, with absolutely 0 monthly fee. Being wireless, the NVR base can be hid to avoid stealing. To work 24x7 with full capabilities, cameras need to be plugged to power outlets within 10ft, or within 25ft with a extension cable. This one-time job avoids dead cameras and frequent battery changing &amp; costs.