2.8~12mm Manual Zoom Varifocal Lens offers a lot more range than cameras with a fixed lens and allow you to adjust the angle of View from 98 degrees to 22 degrees, a smaller lens value will show a shorter viewing distance and a wide angle field of view. A larger lens value will allow for a longer viewing distance but a narrower field of view. It allows you to adjust the angle of View to meet you need.
960H & D1 Realtime High Definition 4 Channel DVR with (2) 650TV Line 2.8~12mm Varifocal Zoom Cameras
Support mobile surveillance by phones with Andriod, Balckberry, WinCE, Symbian, and iPhone ,HDMI & VGA
Support IE browser to remote view and 960H & D1 resolution
Pre-installed 500GB Hard Drive and Pre-made BNC cables
1 Year Warranty and Free Life Time Tech Support From U.S.A.