This set of 216 player stamps, sponsored by the Major League Baseball Player's Association (not authorized by MLB, thus the lack of team uniform insignia) was issued in professional baseball's centennial year of 1969 and was sold in 18 different uncut sheets, with 12 stamps on each sheet. Each individual stamp measured 2" x 3-1/4". There were nine sheets picturing National League players and nine sheets picturing American League players. The full-color stamps displayed facsimilie autographs on the fronts. The backs carried instructions to moisten the stamps and place them in a special album that was also available. Many sheets of these stamps were uncovered by a dealer in the 1980s and they were available at inexpensive prices. - 2006 Standard Catalog of Baseball Cards, 15th Edition.