SF Cable 2.5mm Angled Male to 3.5mm Female Adapter This 2.5mm Angled Male to 3.5mm Female allows you to use your 3.5mm headphones with any 2.5mm audio device. This device lets you connect 3.5mm headphone to cell phone or PDA his device enables you use 3.5mm headphone to listen radio or MP3 (depends on your phone's compatibility) Lifetime Warranty This device enables you use 3.5mm headphone to listen radio or MP3 (depends on your phone's compatibility)