In 1992, Impel Marketing, Inc. held the license for general Marvel trading cards, while Comic Images held the Spider-Man trading card license.
With the 30th Anniversary of Spider-Man making quite a splash, Impel didn't want to be completely left out in the cold, so they cheekily produced this little five-card Spider-Man "promo set".
All cards were portrait, with frame and logos on the front. The back featured the title, description, and a "web-zinger" factoid. Artists were officially credited.
Note that Impel renamed itself to SkyBox International in April 1992. Marvel purchased Fleer in July 1992, and then purchased SkyBox in March 1995 and merged them to form Fleer/SkyBox. So this five-card promo set was the only Spider-Man card set ever produced by Impel.