Simply plug the 200A Tip/Ring Module into a 20A Telephone Set Module Adapter and the Avaya 2420 Digital Telephone can interface with any current analog devices. This module optimizes usability by providing an interface that can connect analog devices, such as your fax machine or TTY/TDD text telephone for the hearing and/or speech impaired, directly to the phone. Note: When any of the expansion modules are connected, you must connect an auxiliary power supply to the telephone. An1151B1 local power supply (material code: 175706) or an 1151B2 local power supply (material code: 177087) with Battery Holdover is recommended.
