Kids who grew up in the northeast in the 1980s were pretty invested in a fad that might have gone unnoticed in warmer parts of the country. Cajoling their parents at department stores during shopping trips, hundreds of thousands of them came home sporting a pair of Freezy Freakies—thick winter gloves that came with a built-in parlor trick. When the temperature dipped below 40°F, an image would suddenly appear on the back part of the material.

Swany America Corporation, which made, marketed, and distributed the gloves, released more than 30 original designs beginning in 1980. There was a robot, a unicorn, rocket ships, ballerinas, rainbows, snowflakes, and various sports themes, though the “I Love Snow” image (below) may have been the most popular overall. At the height of Freezy mania, Swany was moving 300,000 pairs of gloves per year, which accounted for about 20 percent of their overall sales.

Freezy Freakies

“Boys loved the robot design,” Bruce Weinberg, Swany’s vice president and a former sales director for Freezy Freakies, tells Mental Floss. “Above 40 degrees, the image would disappear.”

The secret to the $13 Freakies was thermochromic ink, a temperature-sensitive dye that's been used in mood rings and heat-sensitive food labels and can appear translucent until it's exposed to warmer temperatures. Swany licensed the ink from Pilot, the Japanese-based pen company, after Swany CEO Etsuo Miyoshi saw the technology and thought it would be a good fit for his glove-focused operation. (Though they experimented with making luggage in the 1990s, Swany has predominantly been a manufacturer of higher-end ski gloves.)

Weinberg isn’t sure how Miyoshi settled on the “Freezy Freakies” name—the president is now retired—but says Miyoshi knew they had a hit early on. “After a few seasons, they could tell they had a winner product,” he says. Swany even put advertising dollars into TV commercials, a rare strategy for glove-makers not named Isotoner.

Pilot was able to adjust the temperature at which the ink would become transparent, or vice versa. If kids were impatient, or if it happened to be during the summer, Weinberg says it wasn’t uncommon to find Freezy Freakies stuck in the freezer so they could materialize their art design. “At trade shows, we’d do something similar with some ice or a cold soda,” he says. “All of a sudden, some ice cubes would make it change, and buyers would think that was really cool.”

The Freakies were such a hit that Swany licensed jackets and considered changing the name of the company to the same name as the glove. It’s probably just as well they didn’t: While Freakies lasted well over a decade, by the 1990s, things had cooled. In the new millennium, Swany was down to selling just a few hundred pairs a year. Color-changing ink for coffee mugs or beer cans was more pervasive, wearing down the novelty; knock-offs had also grabbed licensed cartoon characters, which Swany was never interested in pursuing.

The brand was dormant when a company named Buffoonery approached Swany in 2013 to license Freezy Freakies for a crowdfunded revival. This time, the gloves came in adult sizes for $34. The partnership has been successful, and Weinberg says Buffoonery has just signed an extension to start producing kids’ gloves.

“Parents will probably want matching ones for their kids,” Weinberg says. And both might still wind up in the freezer.