COTHXXXXAD01 Universal Headphone Adapter 2.5mm to 3.5mm For audio / music output ONLY, audio input not available: Mic on the cell phone headset will not work with this adapter Adapter converts the phone's own audio output into universal 35mm output 35mm output means unlimited possibilities of device to broadcast the audio sound/music from your phone Adapter allows connection to any 35mm stereo headphone and portable speaker Adapter also allows your phone/PDA to connect to any home stereo system [Note: May require additional RCA Y-Cable] Suggestion: Stereo Headphone / Speaker Adaptor with built-in microphone. Cable Length: ~2 inch / ~5cm.Output: 3.5mm Stereo Socket Compatible with: Audio devices with standard 2.5mm audio socket Connectivity technology : Wired