The history behind the leather stay is tied directly to the working woman. Historically, leather stays were a low or working-class item. There are records of charities making leather stays for poor women so they could be properly dressed. The feel of these is close to a fully boned set of stays, except they very quickly begin to break-in and work with your body. You will notice when you take them off, they hold the body shape.
These stays are based on original examples throughout the 1700s.