Anti-Tip Unit Brkt Assy, SVCE (Pro Series, DF)
  NOTE:    For Wall/Floor Mount Bracket See 821261
Pro Series Use From Serial #17287990 to #18022050.
           Starting With #18022050 See 821541
           Prior to Serial #17287990 See Manual
DF30/48/60 Use From Serial #17288011 to #18021738
           Starting With #18021738 See 821541
           Prior to Serial #17288011 See Manual
 DF36      See 821327