StarTech.com 3.5mm Audio Extension Cable - Slim Audio Splitter Y Cable and Headphone Extender - Male to 2x Female AUX Cable (MUY1MFFS) - audio splitter - 20 cm

Split one headphone jack into two separate jacks. The MUY1MFFS Slim 3.5mm Stereo Splitter Cable/Y-cable features one 3.5mm male and two 3.5mm female audio connectors, splitting a single headphone jack into two.
A practical, cost-effective audio solution, the 3.5mm stereo splitter cable features slim connector molding that fits easily into a 3.5mm headphone jack, even if the iPod /iPhone /iPad /MP3 player is in a protective case.
The 3.5mm audio splitter/Y-cable is backed by StarTech.com''s Lifetime warranty.