The PA-30 can directly drive up to thirty (30) 8 ohm paging speakers or fifty (50) 70 volt paging speakers. The PA-30 provides loud ringing and paging to electronic key systems 1A2 Key systems PABX s as well as No-KSU phones and multiline phones. Paging is accomplished by connecting the PA-30 to a paging port or unused telephone line input (trunk port) of nearly any phone system.