For 15 inch wheels.  This is a used original Ford F150 spare tire carrier and it’s the short version used on trucks that do not have the rear auxiliary fuel tank (the one behind the rear axle).  The trucks with rear tanks use the longer version.  I believe the two lengths (bolt hole to bolt hole) are 39” and 44” respectively.  

 

I believe this fits 1980 through 1994 without rear auxiliary tank but do your own research first and ask any questions prior to purchasing.  

 

It’s used so it’s not perfect but it works well.  Has a slight bend in the center and you can see that spot in the photos.  It doesn't affect its function, but you can also straighten it if you prefer.