You Need Not Wear Another Single Thing!

 "Bon Ton Lingerie Plastique and your frock - that's all!" 
"...does away with overlapping thickness of vest, girdle, brassiere, pantie or bloomer."
 No boning this must have been pretty daring. And not too popular since I can't find any other references for the name 'Plastique'. But maybe some of that was the cost. $12.50 in 1929 is about $168.00 today, a bit pricey.  
Found in McCall's Magazine, October, 1929.