Male Slide-On Plugs pack of 10 plugs These Male Slider Plugs are sometimes referred to as vampire plugs, Gilbert or zip plugs and are made for use with SPT-1 Wiring. These male plugs are great for use with C7 or C9 Light Line or with our lamp cord wiring to create custom extensions between runs of lights. Package of 10 male plugs in greencolor.Polarized male slide-on plug is for use with 18AWG, 7AMP, SPT-1 wiring only (C7, C9 or lamp cord wiring).