[Huck]

Interesting collectible. I collect the postcards and have never seen the registration cards. I don't believe there is much to know. The card is exactly what it states - registration. Register the set and get first dibs on the next series with the same serial number. It was a good marketing sense by Perez-Steele. Today, we give companies our email address. The Perez-Steele postcards was a limited (??) run of 10,000 sets. I would assume living members of the hall of fame or one of their heirs were offered a set (perhaps a freebie).