Men have been stumped by a picture posted on Twitter.
The post has gone viral after Twitter user Aimu shared an image of a small women's health device and wrote: "Since you boys know everything what's this."
Many poked fun at the post, with one man writing: "a teeny tiny crossbow", another suggesting it was "a tiny pogo stick for mice", and a third guessing it was branding for Tesla.
Unfortunately for them, none of these answers were correct.
The picture is actually of an intrauterine device (IUD), which is used as a type of birth control.
They're sometimes known as "the coil" and the T-shaped devices are normally made of plastic and copper. Doctors insert the IUD through the cervix and into the womb.
They slowly release copper or a type of hormone that alters cervical mucus to make it much more difficult for sperm to reach the egg.
IUDs are popular due to their 99 per cent effectiveness in preventing pregnancy. They can last anywhere between three and 10 years before needing to be removed.
It is certainly not the first time men have been stumped by basic questions about women's health on the internet.
There has been an ongoing trend, since about 2016, where women ask men how a menstrual pad works.
One of the most recent viral iterations of this was published on TikTok, with a clip showing user Arianna Romano ask her partner Isaac Turnage about the pads in 2020.
At first, Turnage is confused about how peeing would work.
"How do you pee with the pad on? You can't. You have to take it off first, obviously," he said as Romano laughed.
"Do you just pee in the pad and let it sit in your vagina?"
"What is the pad attached to?" Romano asks him.
"Your coochie," he said.
Romano then explains the pad attaches to underwear.
"Wait a second. Oh, it's not actually on your vagina?" he said "So does it just absorb the blood or not?"