Model:NW-WS410 Series When the going gets tough, the NW-WS410 Sports Walkman is with you every step of the way. Built to withstand the elements, it’s the ultimate training partner. 4GB of storage capacity Water proof (salt water) for worry-free use2 Works in temperatures from -5°C to 45°C Up to 12 hours of battery life3 Ambient Sound Mode BATTERY LIFE - CONTINUOUS PLAYBACK MUSIC Linear PCM(1411kbps) Ambient Sound Mode ON:7 hours(approx.), Ambient Sound Mode OFF:10 hours(approx.), MP3(128kbps) Ambient Sound Mode ON:8 hours (approx.), Ambient Sound Mode OFF:12 hours(approx.) WEIGHT 32 g