Dependable and accurate dual wire monitor for one person and one work surface. The Resistance Ranger Series is the most reliable workstation monitoring system available. The extremely sensitive monitors accurately measure the electrical resistance of an ESD wrist band and work surface and signals if the devices fail. The RangerTWO is an extremely sensitive and reliable ground monitoring instrument. Audible and visible alarms are triggered if the operator’s resistance exceeds 35 megohm. Low resistance of 1.8 megohm also triggers an alarm event. Mat alarm limits are set at 100 meg ohm.