Apple Apple Earphones with Remote and Mic

The Apple Earphones with Remote and Mic take the acclaimed Apple iPod Earphones and add a control capsule, located on the cable of the right earpiece, that includes a microphone and three buttons

Here's what you can do with this convenient remote:
atat Adjust the volume by pressing the + and - buttons.
atat Control music and video playback including play/pause and next/previous by pressing the center button.
atat Record voice memos on supported devices.
atat Answer and end calls.

Compatibility Information
atat The remote and mic are supported only by iPod nano (4th generation and later), iPod classic (120GB/160GB), iPod touch (2nd generation and later), iPhone 3GS and later, and iPad. The remote is supported by iPod shuffle (3rd generation and later). Audio is supported by all iPod models.
atat Requires software version 1.0.3 for iPod nano (4th generation), 2.0.1 for iPod classic (120GB), and 2.2 or later for iPod touch (2nd generation).