Merlin Swim MP3 - 4GB (Swim for HOURS to your own MP3s and WMA music. Stores over 1000 tracks on the 4GB Storage built-in) Guaranteed waterproof player design for international standard IPx7. Audio format: MP3, WMA. Screen: White light LCM. Touch pad: 4 function Keypad & Power switch Keypad. Compliant to USB 2.0 specification (Full Speed). Non-volatile solid-state storage - data retention for at least 10 years.