Girth Belt Question

Quick question, just got my Mohair girth belt but its too long. When you dye this does it shrink? Or is there a way to shrink it? Any help is appreciated.

Dye it in boiling water ,and when you lay it out to dry it don't stretch it
you should lose about 2-3 inches

Thanks. Was going to try the method with the latex stain. Wonder if I just use the boiling water it will shrink. Worth a try.