I have the hardest time finding regular knee high boots that will fit over my very solid and very large calves. I saw a reviewer advise that they took the boots to a cobbler and had them split down the back and laced. So I figured. Brilliant idea.. win win. If they don't fit. I can do that and if they do.. even better. When I put on the boots I was thought there was no damn way they would zip over my calves. They were gaping inches inches. So I pulled the two sides close.. zip. Up a little further.. same treatment. Until.. finally they actually zipped. I was so happy antruly stunned. The stretch is quite amazing. These are beautiful. I would highly recommend. I paid for expedited shipping and got it about 2 weeks sooner so I'd say for $10 more that it was worth it.