Does anyone have is harness?

I don't have this one, but I do use harnesses for my pit bull mix, and my tiny 4lb mutt. Anyway the 40 inches is talking about the girth of the dog around it's largest part of his chest. Just take a measuring tape and place it around the widest part of his chest behind his front legs. This will be the size you need. Most harnesses are the same. It looks like the fleece will help keep him from getting any irritation from the straps under his arms. Good luck.