Bogen's MAX1R Mono Aux Input Module is designed to provide telephone access to most commonly available paging systems. It works with PBX loop, ground start trunk ports, and station ports and is compatible with the full range of currently available telephone equipment, i.e., PABX, standalone 1A2 key, Electronic Key, Hybrid Electronic Key, or CO and Centrex. MODE switches let you select 24V or 48V power supply.