METRIC, 3/8” DRIVE, FLARE NUT, STANDARD LENGTH, CHROME HAND SOCKET.  Flare nut sockets are specifically designed for Lambda probes, featuring an open section that facilitates easy use with wires and connectors. Input Drive Size: 3/8" Drive Shape: Square Length: 70mm Type: Flare Nut Socket Output Size: 16mm Opening: Fla 3/8 Sq. Dr. Flare Nut Metric Chrome Socket in 16mm