Posted By:
fkwIMO Brad got it, it is a cut Rowe Exhibit. The postcard sized cards were designed in 1977, and the cut cards you have are exactly the same. The color is not yellow, Ive only seen a few of the Rowe cards and all have been yellow that I remember. Pennock is listed in the Rowe set as a Red Sox, so Im sure thats what they are. Most vintage sets will show Pennock as a Yankee. He played for Sox from 1915-22, and as a reliever in his last year 1934.
PS. There is at least 1-2 of the Rowe 4-in-1 cards a year on eBay advertised as a "Rare uncataloged Exhibit card". They always seem to be yellow though.