Increase your productivity with 84 additional programmable keys that allow you to complete actions with just a touch. You can link up to three modules together for optimal efficiency. The expansion module comes with an easy-to-read color screen display and attaches directly to the side expansion port, drawing its power directly from the desk phone. Each module provides you with 28 programmable function keys and 3 page buttons. Available for the 6920w, 6930w, 6940w, 6865, 6867, 6869 and 6873 models.