Is your car's brake warning light on? This might be the fix. This is a brand new Vemo brake pad wear sensor (part number V20-72-5127). It's a small but important part that lets your car's computer know when your brake pads are getting too thin. This one is for the rear axle on disc brake systems. The overall length is 883mm, and the warning contact length is 885mm. It's an exact replacement for many European vehicles (like certain Mercedes, BMW, VW, or Audi models). Always double-check that this part number matches your old sensor or your vehicle's requirements before buying. Installing a fresh sensor can turn off that annoying dashboard light and ensure your braking system is monitored correctly. A straightforward, genuine Vemo replacement part.