What is a twin crown needle for?

I looked at the BB needles and I noticed they offer something called a Twin Crown needle. What is that used for? Has anyone tried them?

It works like a "star’ needle and increases production speed- I like them- but I recently switched to forked needles and I like those also- pretty fast production speed on those also. I can get a regular newborn head done in 2-3 days - or about 6 hours- not all at once

What do you mean by increases production speed? Roots more hair into the follicle or doesn’t break?
I used to use the forked needles but switched to crown needles because I found the forked needles could leave more visible holes in some vinyls, especially if you don’t catch a hair.

The twin crown I believe has more barbs- I like it of a fuller head of hair- but I found if you only have a thin strand with few hairs it just increases the rate at which you can root- and you don’t miss. As far as forked needle- I use a full needle pen holder and I generally don’t miss any hairs- so it is fast for me. I bought every type of needle to try them out- and I think it is just a matter of personal choice.