Vintage 1930s Belmont Labs Mazon Soap Box & Quack Medicine Advertising

The listing

Vintage 1930s Belmont Laboratories Co, Inc Mazon Soap for Tender Skin and the Quack Medicine Advertising (Insert Sheet) with Psoriasis Ephemeral Advertising. The ad is printed on both sides. Box is in excellent condition. Insert is in like-new condition. NO SOAP INCLUDED! It was used. My understanding is that the ingredients included harmful and cancerous chemicals, so I was concerned that someone might actually use it.