Hard to open and close. You have to open it by raising the levers before inserting the ends of the wire and then lowering the levers to close it. Don’t use these connectors with very thin wire (24 gauge) since they will break the wire.Two of the 10 connectors actually broke when I was using them. On one, the lever broke off when I was opening it, and on another, when I closed it on a 24 gauge wire, the wire broke off inside of the connector and then the connector would not open after that. The rest of them worked, though I only used them each to make one connection and I can’t vouch for their ability to open/close repeatedly.