Having a ruler in you equine first aid kit can be incredibly helpful when taking pictures to text to your veterinarian in an emergency.
Many times we review pictures of injuries up close. This is great to show us detail. What we lose is perspective. It can be difficult for us to determine the size and assess the severity of an injury. Placing a ruler by the injury can prove beneficial. In addition, take a picture from farther away. This will also help us with perspective.