This issue is a variant of Fantastic Four (Marvel, 1961 series) #398 [Regular Direct Edition]. There exist further variants.
Foil Enhanced Cardstock cover; Glossy interior
2 letters of comment by Joseph J. Kostal, Matt Kuhns.
Total Number Copies Printed (net press run): Average number of copies each issue during preceding 12 months: 231,675. Single issue nearest to filing date: 245,500.