OpenSwim is completely waterproof and submersible, and features four gigabytes of MP3 storage, enabling athletes to train harder no wires, no devices, no limits.Specifications:Frequency response: 20Hz-20KHzSensitivity: 98 3dBCompatible profiles: MP3 | WAV | AAC | WMA | FLACMaximum charge voltage: 5.25 VSpeaker impedance: 8.5?20%Battery: Lithium batteryBattery Life: Up to 8 HoursBattery capacity: 183 mAhCharge time: < 2 hoursWeight: 30g: 2 yearsWater resistance: IP68Features:Designed for SwimmersComfortable & Secure FitFlexible & DurableOrganic Design20% Lighter than TitaniumOpen-Ear DesignIP68 Waterproof (Submerge in water)4GB Memory (Up to 1200 Songs)8 Hour Battery LifeMP3 Player (No need to connect to your phone)PremiumPitch2 Stereo Sound & Enhanced BassEar plugs & Carry Bag includedPackage Contents:1 x OpenSwim MP3 Player1 x Pair of Earplugs1 x Carry Bag1 x Charger