THE BACK
The back is where YOU sit, where the saddle fits, and one of the most sensitive parts of the horse.
It is important to be sure your saddle fits properly as not to sore the horse's back. Sometimes the horse will buck or act up if the saddle is fitting wrong.... it HURTS....
So, if you are unsure, please ask an expert if the saddle is fitting correctly and also to learn how to tighten it properly so you don't lose it and your seat when riding!