Marson Metric Ribbed Rivet Nut Kit, Includes M4, M5, M6 Mandrel & Nosepiece, 50 Assorted Ribbed Style Rivet-Nuts, (12) M57360, M57385, M57384, (8) M57386, (6) M57387, Molded Plastic Case, Weight 2.75lb. (1.25kg)