Bt39s paragon 510 is feature packed with a 200 name and number directory protected by a non volatile memory ensuring contacts are not lost during power failure a sim card readerwriter enables works as a back up device for users contacts should they loose their mobile phone or sim card other features include type 2 caller display 30 numbers call log headset port and hands free function allowing for high quality conference calls either via a headset or by using the speakerphone the handy