BlackBerry Noise Isolating Handsfree Stereo Headset Earphones for T-Mobile BlackBerry Curve 8520 The BlackBerry Sound-Isolating Headset offers a superior sound experience Featuring accurate sound reproduction via noise-isolating ear gels Headset provides clear communication while taking calls and enhanced sound quality when listening A hands-free in-line microphone design blends seamlessly with the headset OEM RIM Blackberry Stereo Hands-free Headset with On/off Button