I have this boot in a 6M Wide Calf 15" circumference.  It is awesome first boot in 15 years I can get my foot and calf in and jeans!  However buyer beware, what they are shipping as the 15" circ is really the 13" version.  Sadly so sadly I had to package mine up and send this pair back.  The ones I bought at the Macy's clearance was a brown 6M Wide Calf 15 inch, and the box was labeled as such.  This description for this one says it is 15" calf, but it is not.  I couldn't even zip it closed, let alone get a jeans pant leg in it.  I really wanted a second pair, but this didn't work out.