In the mid 1950's LS & Co started selling the 501 jeans on America's east coast for the first time. Many folks had already been introduced to the jeans, but to some this button fly work pant was something they had never encountered.
In order to make potential consumers comfortable with the company's products, LS & Co. introduced a zipper version of the button fly shrink to fit jeans in 1954. It had everything long time wearers loved, the silhouette, the tough but flexible fabric, rivets etc.
Note - All sizes listed with the ticket size first and the post shrinkage size afterwards.