Review on MCIGCIM 200Pcs Connectors: Insulated Terminals for Reliable Electrical Connections by Darin Marshall

They are just completely useless, the metal used doesn't crimp properly and no matter how hard you crimp them you can pull the wire out with little effort. I'm just wondering how many people actually tested the coupler after crimping. I feel very little. Don't waste your money, it's garbage.