Brand: Sony. MPN: WH-CH520/B. High quality sound and comfortable, all-day listening in a wireless headphone. The WH-CH520 have an ultra-long battery life of up to 50 hours and a 3-minute quick charge gives you up to 1.5 hours of audio playback. With an adjustable headband, soft earpads and lightweight design, you can find your perfect fit and stay comfortable for longer.