Zeebor presents Famous Pets cards were issued in 1971 by Trebor Sharps Ltd. of London. The illustrated 24-card collection showcases famous animals throughout history. One card was included with each two pence purchase of Trebor Chews. Each card measures approximately 1.46 x 2.625 inches (37 x 67 mm).

The Zeebor from Trebor presents Famous Pets collector album was sold separately for three pence until February 29, 1972. The album was published by Hunter Collier Ltd. A pack of 25 random animal postage stamps was available by mail order in exchange for 20 Trebor Chews wrappers.

"Enos the Astrochimp" and the Mercury No. 9 spacecraft are depicted on card #19. Named after the Hebrew word for "man," Enos is the third hominid and only chimpanzee to orbit the Earth. Enos was launched aboard Atlas LV-3B 93-D during the Mercury-Atlas 5 mission on November 29, 1961.

The chimpanzee completed two orbits before safely splashing down about 200 miles south of Bermuda. Enos removed the medical sensors and catheter before being recovered by the USS Stormes over three hours later. The mission qualified the Mercury spacecraft for the historic orbital flight of John Glenn aboard Friendship 7.

Enos died of dysentery of November 4, 1962. The Mercury-Atlas 5 spacecraft is held by the Smithsonian Institution and displayed at the Museum of Life and Science in Durham, North Carolina.