A disclaimer was a warning cautioning users of a product about the dangers associated with doing so, thereby releasing themselves from liability.
The Tribbles cereal commercial included a disclaimer along the bottom of the screen warning consumers about choking hazards of tribble fur; to shave the tribbles with the Edward brand tribble razor, that Edward Cereals LLC was not responsible if the tribbles reproduced in your digestive tract, and to chew the cereal thoroughly. (ST: "The Trouble with Edward")