Even though the 5510 was revolutionary, it technically wasn't the first phone with an MP3 player. The Siemens SL45 introduced this feature almost 4 months before, in August 2001! : r/vintagemobilephones
Siemens SL45: первый MP3 в сотовом (2000) – ретроспектива - YouTube
Jual Siemens SL45 / SL45 original Mp3 player Jadul | Shopee Indonesia
SIEMENS SL45 - Petra Riedmueller
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SIEMENS DUAL BAND GSM PHONE, 110220Volts.com
Podróż w czasie: Siemens SL45, czyli pierwsza komórka z MP3
Siemens SL45 photo gallery :: GSMchoice.com
Siemens sl45 piękny adapter mp3 cały komplet | Warszawa | Kup teraz na Allegro Lokalnie
Mp3 Player; Play - Siemens SL45 User Manual [Page 27] | ManualsLib
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Page 3 | Siemens SL45 Reviews, Compare Siemens SL45 Mobile Phone Reviews at Review Centre.