ISECUREtrac [ISRE], an Omaha, Neb.-based Global Positioning System (GPS) tracking service, signed a three-year agreement with Pennsylvania Adult Probation and Parole to supply the county with its tracNET24 criminal-justice tracking units. The system is used to monitor the whereabouts of offenders. Financial terms were not disclosed. Beaver County initially will deploy 30 passive GPS tracking units on their adult offenders.