求翻译：型号是指鞋子的相近两个尺码之间宽度的差值，（如，40码于39码鞋的宽之间差），这个参数通用来标示相同长度鞋的横向宽的大小，也就是说用来标示脚宽度与围度的。是什么意思？

Model is similar to the shoe width difference between the two sizes, (eg, 40 yards to 39 yards difference between the width of the shoe), this parameter is common to mark the same length of the horizontal width of the size of the shoe, that is used to mark the width and circumference of the foot.