4mm Safety Jack (socket) accepts sheathed or shrouded banana plugs and meets the latest international safety standard IEC 61010-031 to 1,000 V CAT III and 600 V CAT IV. Round panel nut allows for compact placement and assembly. Termination is with a M4 threaded stud with 2 hex nuts. Materials: Body: Polyamide (Nylon); Jack and Nut: Brass, Nickel Plt. Body Thread: M12 x 0. 75mm. Maximum Panel Thickness: . 40" (10mm). Available in 9 colors. Use assembly tool Model CT2246A. Sold in package of 50.