ESSEX GLAM Womens Long Over The Knee Open Back Boots Synthetic Synthetic sole Shaft measures approximately 21.5 Inches from arch Stunning Womens Thigh High Low Heel Winter Boots 21.5 Inches / 53.75 CM Shaft Height 14.5 Inches / 36.25 CM Calf Circumference 15.5 Inches / 38.75 CM Shaft Circumference (Open Top Back) This style is labelled with UK/EU size but this will be equivalent to the US size ordered. E.G US5/UK3, US6/UK4, US7/UK5, US8/UK6, US9/UK7, US10/UK8, US11/UK9