WOT IS IT??
No prize if you guessed it is a USB device.
-Not a receiver for a mouse or keyboard.
-Not a Bluetooth device
-Not a WIFI adapter
It's a "Super Mini USB 3.0 1TB Thumbdrive."
Yes, a Terabyte. That's approximately 1,000 Gigabytes.
Note the size, resting on a single standard keyboard key.
$14 and a $3 shipping. From China. Look for it on wish.com
Now, before you get all crazy and get one and store EVERYTHING on it, beware that not all cutting edge cheapo storage devices hold up. Some even fake the capacity. Some just stop working.
More annoying is that some simply sell out, only to resurface much later...or never.
Also, if you search for "1 TB" you will find all kinds of shapes and sizes, perhaps one that will better meet your needs, such as not having one so small the dog could swallow it.