Viking Paging System with Amplifier and Speaker Horn Fully Powered for Use with Office Phones Complete system with high quality weather resistant paging horn/speaker and power supply included. The system is LOUD and CLEAR (built in volume control can be used to adjust volume independently between paging and ringing). Connects paging from your office phones directly out to the speaker. Also allows phones to ring on speaker if desired. Everything you need to add Paging and Multiple Line Loud Ringing to Any Phone System. Paging is accomplished by connecting the PA2A to a paging port or unused telephone line input (trunk port) of nearly any phone system. Designed Manufactured & Supported in the USA! 2 Year warranty NEWEST VERSION: There are a lot of older versions out there that will not work with cable, VoIP, channel bank, etc phone services