"Millions of women trust the power of a Promise-High -Waist to slim away inches, smooth away figure imperfections. Now they can complement it with the ideal bra, new Promise Bra with gentle Biaband control. This exclusive feature within each cup makes the most of a small boson, minimizes and contours the full bosom. The next time you select your personal wardrobe, put two Promises together. They add up to the most elegant figure you've ever had. That's a Promise."
Here's another Poirette ad from 1961 showing the undergarments and then fully clothed