The Model LGF-2 gypsum moisture meter is a two-range version of the Model LGF. The second (low sensitivity) range is used on High Density gypsum plaster board to prevent off scale indications that can occur with damper boards. With the switch in the OFF position, the operation is identical to the Model LGF. With the switch in the ON position, the instrument has ½ the normal sensitivity, thus allowing off-scale indications to be accurately read. As an example, assume that the off-scale indication was caused by a signal that was 1.5 times the signal that would have indicated 50 on the panel meter (75). With the switch in the ON position, the signal will now be indicated on the panel meter as half of 75, or 37.5. Complete with a Carrying Case, NiMH Battery and Operating Instructions Book.