The Sharper Image SHP921-2 Wireless Headphones lets you enjoy superb sounds from your mp3 players, stereos, and TVs without the struggle of tangled and cluttered wires. This awesome headphone provides high frequency RF, ensuring you clear and stable receptions ranging to up to 100m. Its wealth of features also includes a built-in FM radio that enables you to listen to your favorite radio stations, and a 10-hour battery life that is just perfect to bring along trips.