Abstract: A method and apparatus for adjusting an electrical characteristic of an electrical component of an electrical network which network comprises a stack of secured together foils or layers which include one or more synthetic foils each having a metal layer on one or both surfaces and a cover foil and has connecting wires which are fused through the cover foil and welded to the desired spots on a metal layer characterized by trimming at least one of the metal layers to obtain the desired electrical characteristic by directing a laser beam through at least one foil and focusing the beam on the metal layer being trimmed. To prevent inadvertent and undesired trimming of a metal layer while trimming a given metal layer, one of the synthetic carrier foils may be of a material which is impervious to the laser beam or may be provided with a reflective metal layer.