AP02 Transfer Case Chain 42 links for ML-Class W164, GL-Class X164, R-Class W251, and V251 vehicles equipped with Steyr single-speed transfer case.Compatible with models including ML 280, ML 300, ML 320, ML 350, ML 400, ML 450, ML 500, GL 320, GL 350, GL 420, GL 450, GL 500, R320, R350, and R550.Fits vehicles manufactured 2003 onward for W163 and W164 ML-Class (US-spec only, Steyr single-speed transfer case), 2006–2012 for X164 GL-Class (US-spec only, Steyr single-speed transfer case), and 2007–2011 for W251 R-Class.Not compatible with non-US models equipped with off-road package two-speed transfer case or distributor.Matches OEM part numbers HV091, HV-091, 2512800800, A2512800800, 2512800900, and A2512800900.Designed as a direct replacement to restore function and fitment.