This is heavy duty, stretch resistant latigo leather that will not rub or irritate your horse's sides like nylon.  It already has the holes, so it can be tied or used with the post of a cinch.  Technically, for the comfort of your horse, all the parts touching your horse should be as natural as possible, so when in doubt, leather, wool, or felt is far superior to any sort of man made material.  Also, your saddle should have two of these, verses an off billet.  Off billets are much less safe because the leather always wears in the same place, and they use only one layer of leather.  Where as a latigo will distribute the pressure evenly over all of the wraps between the saddle and the girth, and there are at least two layers of leather holding the saddle.