The Sony MDR-XB50BS earphones combine an elegant, sports-friendly design with powerful, bass-heavy sound. With the Sony EXTRA BASS technology, these earphones deliver a sound thats rich in low-end and perfectly suited to bass-heavy genres like EDM or hip-hop. EXTRA BASS works by accentuating certain low-end frequencies, adding a real punch to your favourite tracks and giving you that much-needed energy boost while exercising. Never be without your music again. Bluetooth connectivity lets you run, jump, kick and more, without wires holding you back. Ergonomic arc supporters keep the headphones securely in position while you exercise. Bluetooth connectivity lets you listen for up to 8.5 hours without wires getting in your way. Enjoy music even while running in light rain, thanks to the IPX4 splash-proof design. 12mm driver. Bass control. Batteries required 1 x rechargeable battery (included) .