Except as otherwise provided in this chapter, any commodity in package form introduced or delivered for introduction into or received in intrastate commerce, kept for the purpose of sale, or offered or exposed for sale in intrastate commerce shall bear on the outside of the package a definite, plain, and conspicuous declaration of (1) the identity of the commodity in the package unless the same can easily be identified through the wrapper or container, (2) the net quantity of the contents in terms of weight, measure, or count, and (3) in the case of any package kept, offered, or exposed for sale, or sold any place other than on the premises where packed, the name and place of business of the manufacturer, packer, or distributor as may be prescribed by regulation issued by the Secretary; provided, that in connection with the declaration required under clause (2), neither the qualifying term “when packed” or any words of similar import, nor any term qualifying a unit of weight, measure, or count (for example, “jumbo,” “giant,” “full,” and the like) that tends to exaggerate the amount of commodity in a package, shall be used; and provided further, that under clause (2) the Secretary of Agriculture shall, by regulation, establish (a) reasonable variations to be allowed, which may include variations below the declared weight or measure caused by ordinary and customary exposure, only after the commodity is introduced into intrastate commerce, to conditions that normally occur in good distribution practice and that unavoidably result in decreased weight or measure, (b) exemptions as to small packages, and (c) exemptions as to commodities put up in variable weights or sizes for sale intact and either customarily not sold as individual units or customarily weighed or measured at time of sale to the consumer.