Tiffany sets are the premium editions Topps issued from 1984 to 1991 — including the 1989 and 1990 Bowman Baseball sets. Officially branded as "Collectors' Editions," the hobby gave them the "Tiffany" nickname, and it stuck.
What makes Tiffany sets special? They're identical to the regular issue sets but printed on higher-quality white cardboard stock with a glossy finish on the front. The result is a noticeably sharper, cleaner card that stands out immediately next to the standard version.
Tiffany sets were sold exclusively as complete factory sets, which means you can't just pull them from packs. They were produced in much smaller quantities than regular sets, making them legitimately scarce and highly valued by vintage collectors.