Spec Sheet Preview: Although only the size and weight of a conventional telephone handset, the AA918GY combines all the essential functions needed for effective internal communication in one compact unit: hands-free loud-speaking and confidential total privacy. It is designed for a desk use or wall-mounting using an optional wall bracket (model GF934). On the desk or wall, it permits the user to converse with the caller, hands-free, from anywhere in the room. Master is designed to work with the RM5000EX or CB901EX series microprocessor inte …