, High qaulity Memory:4GB Music Format: MP3, WMA formats USB: 2.0 Waterproof Rating: Standard IPX8 Battery Life: Playing continuously for 8~9 hours(depending on user's operation habits) Film ware updating, file transmission and storage, and battery recharge via USB Temperature Rating: 0 - 50 C Humidity: 20% - Dimensions :60*21*21 mm(Lx W xH) Systems: 2000/XP/Vista/7.0, OS 8.6 or later Button Controls: Forward, Back, Play/Pause, Volume Up, Volume Down Made of high durability aluminium casing with anti-scratch finish Suitable for Swimming/ /Sauna /Spa /Surfing /Snorkeling /Running/Windsurfing/Rafting/Hiking/ Beach and other water activities * Package Contents: 1x 4GB Underwater Sport Waterproof Swimmer MP3 Player Black Note:Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.