The affected vehicles are 2006 to 2012 model-year Volvo C70 convertibles built from November 15, 2005, through July 31, 2011, and 2011 to 2012 model-year Volvo S60 sedans built from July 14, 2010, through April 16, 2011.
Note, it is only those vehicles fitted with the optional accessory spare tire kit, which according to Volvo is around 19,600 vehicles in the U.S. alone.
These vehicles fail to comply with the requirements of federal motor vehicle safety standard number 110, which concerns tire selection and rims. These vehicles do not contain the correct information for the optional accessory spare tire kit, which means owners could inflate the tire to a level that could result in it failing.
The solution is simply to swap the incorrect label with a correct one, which Volvo dealers will do free of charge.
If you own one of the affected models, you can contact the NHTSA at 1-888-327-4236 (reference recall campaign number 11V508000) or Volvo customer relations at 1-201-768-7300.