At first glance, it looks strange, almost unsettling. Two clear red balls, connected by strings, each with a solid red line suspended inside. No obvious function. No instructions. When photos of this object began circulating online, thousands of people guessed wildly. Medical device. Fishing gear. Some kind of ritual tool. Even engineers and collectors were split. For a while, the internet genuinely couldn’t agree on what it was.

The mystery lingered because this object comes from a time most people barely remember — and many never experienced at all.

The answer is far simpler than the theories.

This is a vintage clacker toy, popular in the late 1960s and early 1970s.

Clackers were a massive craze. The toy consisted of two hard plastic or acrylic balls attached to strings, connected by a small ring or loop at the top. You’d hold the ring and swing the balls up and down so they smashed together, creating a loud “clack-clack” sound. Kids competed to see who could go fastest without losing control. Some versions were solid plastic. Others, like the one in the photo, were liquid-filled, which is why you see that red line floating inside — it’s a sealed tube or dyed fluid designed to make the motion more dramatic.

The liquid-filled versions were considered the “cool” ones. The moving red stripe made the toy hypnotic when swung, especially in sunlight. That detail is exactly what throws modern viewers off. Without context, it looks engineered or technical. But it’s purely visual flair.

Clackers eventually disappeared for a reason. They were dangerous. The balls could shatter on impact, sending sharp plastic shards flying. There were injuries, broken wrists, and plenty of emergency room visits. Schools banned them. Parents threw them out. By the mid-1970s, they were gone.

That’s why so few people recognize them today. If you didn’t grow up during that short window, you’ve probably never seen one in real life.

So no — it’s not medical equipment, not a weapon, not a scientific instrument. It’s a forgotten toy from a loud, reckless era when safety standards were… flexible.

And now that you know, you’ll never unsee it.