The Ground Level Meter COB by Slink injects a programming tool. It can be moved by clicking on the top left-hand part of the tool. The numerical display is updated by pressing in the center of the meter. The first number displayed is the number of ground levels defined in the sfc world file in use. The second number is the number of pixels in each segment of ground level. The third number is the ground level at that east-west location. The Ground Level Meter uses the C1 class numbers 3 6 210.