Axxess Select GM Models 2019-UP Add-A-Sub Data Interface
Axxess provides a simple plug-and-play solution for adding an aftermarket subwoofer to select GM vehicles. The patented Add-A-Sub™ interface (AXSUB) restores and extends the low-frequency response that is often limited by factory radios, delivering stronger, more accurate bass so your subwoofer can perform at its full potential.
