They were rocks packaged in custom cardboard boxes[1] complete with ventilation holes and straw bedding imitating a pet carrier.

Although by February 1976 they were discounted due to lower sales, Dahl sold over one million Pet Rocks for $4 each,[1] and became a millionaire.

[10] To promote the film, Sabec Limited released an official Pet Rock video game for Nintendo Switch.

[18] During the travels of the Perseverance rover on Mars, NASA scientists had observed around Sol 341 (February 4, 2022) that a small rock had dropped into one of its wheels.

The rock has since stayed on Perseverance's wheel for around 427 sols (439 days) as the rover traveled over 6 miles (9.7 km) on the Martian surface.