Complex sentence: Each packet contains 31.8 Grams, and until recently were made from the traditional crisp packet plastic that allows for a window to view the crisps with each packet emblazoned with the words "See What You Buy" on the front.
Split into simpler sentences: Each packet contains 31.8 Grams, and is made from the traditional crisp packet plastic that allows for a window to view the crisps. In fact, each packet is emblazoned with the words "See What You Buy" on the front.