Hall's hair renewer is probably one of the most famous quack products of the 19th century. Reuben P. Hall started selling his Vegetable Sicilian Hair Renewer around 1864 and it was still available in the 1930s. Hall's Hair Renewer had stiff competition from the other big name hair snake oil of the day Ayer's Hair Vigor. In fact Ayer bought Hall out in 1870 but continued to sell the brand alongside his own making Ayer a market leader in quack hair products for several years until others got in on the action in the 1880s.

According to Hall himself the product formula was given to him by an Italian sailor hence the name Sicilian Hair Renewer. However the actual product formula changed over time. Initially the formula was composed of 60% water, 36% glycerine, 2% lead sugar, and trace amounts of sulfur, sage, raspberry leaves, tea, and oil of citronella. Later on though the formula was 52% water, 26% glycerine, 13% Jamaica rum, 7% bay rum, and trace amounts of lead, sulfur, and salt. The lead combines with the sulfur to form lead sulfides that darken the hair shaft. However, lead is also poisonous and the Massachusetts Board of Health reported several instances of lead poisoning from products including Ayer's and Hall's hair products (Thirty fourth annual report of the Massachusetts state Board of Health, Boston, 1903). This is probably the reason for the drop in lead concentration in the early and later formulations of Hall's Hair Renewer.

Trade cards like the one below were a popular form of advertising for Ayer. The back of the card would extoll the virtues of the product saying "Old age with its white hair is becoming, but grayness or baldness of a young or middle-aged person is neither becoming nor natural, and indicates premature age. To overcome this the bacteria which destroys or injures and weakens the roots of the hair, should be extirpated from the scalp, and Hall's Hair- Renewer was invented for this very purpose and to renew the hair and its youthful color again. The Renewer acts directly on the roots, supplying them with needed food and color matter, annihilates the bacteria or infinitesimal animal that does so much mischief; consequently prevents the hair from falling and restores its vitality and original color, and also cures dandruff, tetter, and all scalp sores. It the scalp is not shiny bald and the hair follicles destroyed, then the new hair of a natural hue can be made to grow again on the bald places by a timely use of Hall's Renewer. As a dressing it keeps the hair lustrous, soft and silken, and easy to arrange. Merit wins."