In 1973 National BSA did a major "upgrade" to all of their patches. The patrol patches stayed at 2" in diameter but not had a "rolled edge" border and were in full color. Over the years several color variations existed but there were notably a few distinct back materials used. The first was a "gauze" or mesh back and a full rolled edge. Then the same mesh back with a "flat back rolled edge" was made. They then added plastic to the back and it became know as the plastic/gauze back. Then there was a change to a paper type backing. Finally they made a clear plastic back. Several color varitations on some patrol patches exist in each type of backing.