Review on Ancable 2-Pack 6-Feet Mono Cable 2.5mm Male to 3.5mm Mono Jack Plug - 12V Trigger Cable for Parasound Amp and Logitech Harmony Hub: High-Quality Connectivity Solution by Alyssa Bennett

While I'm sure this particular cable has a different purpose, it does exactly what it says it will do. This is the mono cable used on older Parasound models. The device acts as a trigger to turn on a third party amplifier (or even a newer Parasound device) with a standard 1/8" jack. In my case I am using a cable on a Parasound NewClassic 2100 preamp for another brand of amp. Works like a champ. Not very picky about configuration (mono) but works great in this application.