CableChum® offers the 3.5mm Mono Male to 3.5mm Stereo Female Adapter
This adapter consists of a 3.5mm mono male on one end and a 3.5mm stereo female on the other. It is typically used to convert a 3.5mm stereo male cable to a 3.5mm mono male cable.
|3.5" Mono Male
|3.5" Stereo Female