Sony NWZ-WS615 Waterproof 16GB WS Series Sports MP3 Walkman. Train hard with no interruptions. The NWZ-WS615 Series waterproof Walkman features a lightweight, wrap-around headband that will hold tight whether you’re in the pool or on the track. NFC and Bluetooth connectivity makes listening easy, so you’re free to focus on your workout. And buy this Sony NWZ-WS615 Waterproof 16GB WS Series Sports MP3 Walkman® with NFC & Bluetooth and Remote Control for Swimming and Running Now £169.00.