I didn't have a through crimp when I bought these plugs. After crimping with a standard crimping tool, I couldn't press the wires against the edge hard enough for the plug to seat properly in the keystone. Bought a VCE Ethernet RJ45 crimping tool for pass-through connectors and they worked like clockwork. It's a lot easier to just keep the wires straight and fully load the jacket, but I have years of experience so I only use it for Cat6.