For the fifteen consecutive years, PENPEX was held at the Community Activity Building (CAB), 1400 Roosevelt Avenue, Redwood City on December 6-7, 1997. The Peninsula and Sequoia Stamp Clubs along with the Redwood City Recreation Department sponsored the show.
The show theme was the 50th Anniversary of the Sequoia Stamp Club. Show cachets sold for $1.50 each.
1997 Show Cachet signed by PENPEX jury
The show had 71 frames of exhibits of 12 pages each. The jury members were Martin H. Feibusch, Dr. Donald E. Green, Leonard Holmsten, and apprentice Vesma Grinfelds.