WALKMAN NWW-S413B is an excellent MP3 player designed especially for sports enthusiasts. Its wireless design and improved ergonomics make it ideal for jogging, weight training, and even swimming. The player is waterproof and resistant against salt water, so you can take it with you into the pool or the sea and even dive to a depth of 2 m for 30 minutes. It has no extra cables to get in your way and special manufacturing material ensures that the headphones will stay in your ears even during fast and unexpected movements. The Ambient Sound Mode uses microphones on the left and right side of the device and lets you hear a degree of external sound. This is particularly useful during training, when you need to hear your instructor. Another neat feature is Quick Charge, which lets you charge the NW-WS413 for just 3 minutes to get a full 60 minutes of use. Normal charging (takes about 1.5 h) gives you about 12 h of battery life.