As of 2004, the Torsen differential has become much more accessible. In addition to Zexel Torsen, a company named Quaife now produces automatic torque-biasing differentials. ATBs are manufactured for virtually any car, from the original Mini to the Viper SRT-10. A Torsen or Quaife differential for a Ford Focus, for example, can be had for under $700, and requires little modification to install.