Gilbert plugs are part of many of our Get This Look materials lists. They are required when custom C7/C9 cords made with 18 SPT-1 or SPT-2 lamp cord style cords are “cut to fit”. Short Answer: These plugs work ONLY with a C7 or C9 traditional parallel-wired cord like the cords in this category. They… Read more… How many gilbert (vampire) plugs do I need to order?