I am in the process of placing an order to buy my horse a new blanket. The horse is not currently here so I can't measure him like I normally would to find blanket size. I do have his old blanket here but the tag with the size info is no longer readable. Where exactly on the blanket should I measure with the tape measure to find out what size it is?

Measure from the edge of the fabric that would lie in the center of the horse's chest chest to where the blanket ends at the tail. Basically just fold your blanket in half the long way and measure from one end to the other.