Security surveillance camera, the camera's 60 shell and 90 shell difference is not 60, shell than 90 shell much smaller?
The 60 housing is 60mm in diameter and 90 in shell diameter 90mm. 60 shell --30 meters infrared small gun, 90 shell --50 meters infrared big guns, there are some differences.
The 60 housing and the 90 housing are said to be mm in diameter of the camera. Generally, if the shell is small in millimeters, the distance he can reach will be relatively small
60 and 90 are the diameter of the shell, and the 60 case is much smaller than the 90
