Executive digital proprietary telephone, with 3 line back-lit display, 24 programmable keys and full duplex speakerphone. pure performance - attractive design: panasonic offers a wide line-up of digital terminals with an ergonomic design for all use. the kx-dt500 series digital proprietary telephones take you to a new dimension in audio experience through excellent voice quality audio on every phone, combined with easy access to powerful supportive features and applications.