Stamping of weights or measures on sealed containers.

No person shall sell, offer for sale, expose for sale, or have in his possession for sale, any article contalned in a sealed package or container unless such package or container bears thereon, or on a label securely attached thereto, a description of the net weight or measure of the article contained therein: Provided that the provisions of this section shall not apply to an article sold, offered for sale, exposed for sale or in possession for sale which is not ordinarily sold in transactions for trade or commerce by weight or measure.