PQ25  platform, the same platform used in the  SEAT Ibiza  Mk4 and the  VW Polo  Mk5, [9]  and in its development Audi has collaborated with  SEAT . [10]  The A1 uses a MacPherson strut  front and  torsion beam  rear suspension. [11] The 100,000th A1 was produced in June 2011. [12] UK