Passive GSM Monitoring Unit (PGMU) is the most advanced portable GSM interception and monitoring system that currently exists worldwide. It is portable, fully passive, monitoring of GSM communication.

PGMU operates with all varieties of GSM networks, with all frequency bands, and both A5/2 and A5/1 encryption.

No cooperation with the network operator is needed. In fact, from the service provider's point of view, PGMU interception is completely undectectable and its operation is fully transparent. No transmission is performed.