Chips (Chip Domains)
Chips are LLLL.com domains made up of the letters Chinese buyers consider "premium," which means no A, E, I, O, U and no V, a letter that doesn't appear in Pinyin. Something like XKMZ.com is a chip. XAMZ.com isn't.
The category was born in the 2015 and 2016 rush when Chinese investors bought short .coms as a store of value and prices for chips went from a few hundred dollars to several thousand in months. Then the market cooled and a lot of people who bought at the top learned what illiquid means.
They still trade, at a fraction of the peak, and they're still one of the more liquid things you can own in domaining. Just don't assume the 2015 chart is coming back. It was a bubble, and it popped.