telephones used with private radio services
(4) For purposes of this subsection— (A) the term “essential telephones” means only coin-operated telephones, telephones provided for emergency use, and other telephones frequently needed for use by persons using such hearing aids; (B) the term “telephones used with public mobile services” means telephones and other customer premises equipment used in whole or in part with air-to-ground radiotelephone services, cellular radio telecommunications services, offshore radio, rural radio service, public land mobile telephone service, or other common carrier radio communication services covered by title 47 of the Code of Federal Regulations, or any functionally equivalent unlicensed wireless services; (C) the term “telephones used with private radio services” means telephones and other customer premises equipment used in whole or in part with private land mobile radio services and other communications services characterized by the Commission in its rules as private radio services; and (D) the term “secure telephones” means telephones that are approved by the United States Government for the transmission of classified or sensitive voice communications.