Rather disappointing in these, I buy Ancor as I'm a Marine Electrician, and decided to take a chance on these. They are not up to spec, they do not shrink down small enough to close on 22-20 gauge wires. I have a multiple heat guns, tried them all, rotated the wires, distributed my heat correctly across the connector. No dice.They would not close down enough so I had to pinch them with pliers while they were still hot to get them to seal. Now I have 200 of them.