The very earliest cars used the Magneti Marelli B-5 coils. These coils were black and had the mounting bracket spot welded onto the black metal can. The B-5s had a small vertical slot on each side of the mounting bracket. The end tabs of the aluminum tags were inserted into the slots on the mounting brackets. Rivets were not used on these tags. These coils were used on only the earliest cars in the late 1940s and early 1950s. Etched Magneti Marelli B-5 coil tags.
Ferrari made a small series of Super cars in the late 1950s. The larger engines required a larger filter element and a different tag was used. This one has the word “RETEX” (net or filter) in the center of the top line. Super America crescent-shaped air cleaner tag.