This product is a certified refurbished OEM Audi radio amplifier amp with manufacturer part number 8R1 035 223 A / 8R1035223A / 8R1-035-233-A. It is compatible with Audi A4, S4, A5, and S5 models from 2009 to 2017. The unit has 8 channels and is stocked under 0358. The product is made in Germany and comes with no warranty.