Whenever a commodity in package form is advertised in any manner and the retail price of the package is stated in the advertisement, there must be closely and conspicuously associated with the statement of price a declaration of the basic quantity of contents of the package as is required by law or regulation to appear on the package, except that this section must not apply to products for agricultural or horticultural use where the custom is to state the number of objects or amount of area that can be treated per package unit and the number or area is stated. Where the law or regulation requires the declaration of net quantity to appear on the package in terms of more than 1 unit of weight or measure, only the smallest unit of weight or measure need be stated in the advertisement. In connection with the declaration the qualifying term “when packaged” or any other words of similar import, or any term qualifying a unit of weight, measure or count, for example, “jumbo”, “giant”, “full”, “approximate”, and the like that tends to exaggerate the amount of commodity in the package, must not be used.