You are talking about a Hotpoint Electric sink. These were sold as replacements for kitchen sinks that were hung for the wall and had no cabinet space under them. The cabinet under the sink was for storage of kitchen cleaning supplies and, in models with the garbage disposer known as the Hotpoint Waste Exit, it hid the disposer from view. Manufacturers began discontinuing these as more kitchens were built with sinks mounted in countertops. When a friend's GE electric sink finally had to be replaced in the mid to late 60s, she only found two brands still available: the KitchenAid and surprisingly, a model from Frigidaire which she chose.