You can, mine worked fine. its really been just collecting dust for a min. I hooked it back up a few months ago, when I sold my last HU and reinstalled my factory HU. Im really just trying to get rid of it so I can get a distrubtion block, but if it dont sell, its cool.
If you (1) have a older HU that does not have RCA outputs, or (2) you have a stock HU and want to add RCAs to it to run to your amps. It converts the HU's speaker outputs into RCAs so you can run into your amps. Really usefull if you have a newer car with a HU thats intergrated into the dash with the climate controls.