Any person who sells, attempts to sell, offers for sale or assists in the sale of any goods, product or output, and who willfully and falsely represents such goods, product or output to be the goods, product or output of any dealer, manufacturer or producer, other than the true dealer, manufacturer or producer, or any member of a firm or any officer of a corporation, who knowingly permits any employee of such firm or corporation to sell, offer for sale or assist in the sale of any goods, product or output or to falsely represent such goods, product or output to be the goods, product or output of any dealer, manufacturer or producer, other than the true dealer, manufacturer or producer, is guilty of a misdemeanor and punishable by a fine of not less than one hundred dollars ($100) or more than six hundred dollars ($600), or by imprisonment in the county jail for not less than 20 or more than 90 days, or both. This section shall not apply to any person who sells or offers for sale under his own name or brand the product or output of another manufacturer or producer with the written consent of such manufacturer or producer.