FIRST THING Two have these Fans have been Made and Named Garrison this fan takes a Two Piece Arm. It has a Part Number AC438ACU It's on the Back of the Arm  Double Click on these 5 Pictures they will enlarge.   Taken from a 52 inch  Hampton bay ceiling fan Garrison made in April 2007. This Arm is Silver in color.  I have listed the UPC number above you can use this to see if this arm will work for you. You can find your UPC number on top of your ceiling fan silver sticker. This listing is for one Arm with the hardware. Shipping is Nonrefundable so Please Measure      #188