Your weirdo hats. And even depending on where they're from, they're very hard to screw up.
It has a spring, it has a molded plastic cover over the spring and when you twist it the wires gather underneath. Things that either work or don't work, rather than having varying levels of functionality.
Pros
Internal spring insert can keep the wire connection stable, which can ensure the highest degree of electricity safety and stability when connecting and using the wire. We recommend twisting the conductors first, which will make the connection more secure and strong.