20-18 Ga. Female Metri-Pack Terminals, 150 Series, Pull-to-Seat #12103881 Metri-Pack terminals are different from Weather-Pack terminals in that the male terminals have flat pins, similar to a quick disconnect, rather than Weather-Pack's round pins. Easily determine the Metri-Pack series by measuring the width of the flat pin. Metri-Pack 150 series = 1.5 mm pin width. Metri-Pack 280 = 2.8 mm pin width. Metri-Pack 480 = 4.8 mm pin width. Metri-Pack 630 = 6.3 mm pin width.