Sony MDR-IF240RK Wireless Headphone System System has 24-foot range and lasts up to 35 hours Simple battery recharging High-powered ferrite magnets generate superb sound Weighs 6.3 ounces Sony Mdrif240Rk Ir Headphone Kit Go wireless with your music. The MDR-IF240RK wireless stereo headphone system features 30mm drive units for deep bass, up to 30 hours...