Device Details


The Dual Mono-Stereo Adapter provides a way to connect two assistive switches with standard 3.5 mm mono plugs to a single 3.5 mm stereo input on a compatible assistive technology device. This device is functionally equivalent to a 3.5 mm TRS to Dual 3.5 mm TSF Stereo Breakout Cable (Amazon Link, ~$16).


To use the Dual Mono-Stereo Adapter, connect the two assistive switches to the mono inputs labelled L (left) and R (right). Then use a stereo male-to-male audio cable to connect the adapter to the AT device’s 3.5 mm stereo input.

The Dual Mono-Stereo Adapter can also be used with the LipSync Switch Input Module.

Build Instructions 

The Dual-Mono-Stereo Adapter consists of some electronic components and a 3D printed enclosure. Detailed build instructions can be found in the GitHub link.

Skills Required 

  • 3D Printing
  • Soldering 


  • Soldering Iron
  • Solder
  • Wire Strippers


3D Printing 

Print the top and bottom enclosure pieces following the 3D printing guide. 


Design by Makers Making Change