The seat occupancy mat is a sensor mounted in the front passenger seat.The emulator simulates a situation of a person sitting in the passenger seat with a seat belt fastened.To make the emulator work you need a diagnostic tool (like for , , etc.) to remove old errors of a broken seat mat that are stored in the control unit. Once you connect the emulator your diagnostic tool will be to remove old errors and turn off the SRS/ warning. Unfortunately, the errors related to the safety systems are not removing automatically.Before purchase, please scan your car with a diagnostic tool to make sure your SRS/ warning is caused by a defective seat mat.for C-Class W203 Saloon/Sedan (2000-2004) before faceliftfor C-Class S203 Estate (2000-2003) before faceliftfor C-Class CL203 Sport Coupe (2000-2008)for CL203 (2008-2011)for CLK W209/C209 Coupe (2002-2004) before faceliftfor CLK W209/A209 Cabriolet (2002-2004) before faceliftMaterial:Plastic + Metalcolour:As shownPackage Contents:1 * Bypass emulatorOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.