Does anyone know how Marigold Hunt Coats are sized?

I would like to know what "street clothing" size is equal to a Marigold 12R Hunt Coat. I think the R stands for "regular" but is it length? What is the 12? Thanks in mortgage!
Horse framing & attitude problems..?
Answers:    check out the web site "showmeagain.com." They have a size 10R & they give the bust,waist,arm length,backbone length & shoulder to shoulder measurements for this size. This web site sells "gently worn" hunt coats at reduced prices & whether a coat was only worn a few times, it should be good as different. Nowdays it helps to save money when buying riding clothes,etc
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