Valerie, If the application is high frequency, then your customer may be more interested in the plating material. As signal frequency increases, the signal concentrates less and less in the center of the conductor and moves to the surface of the conductor. The amount of penetration in to the conductor is called the skin depth and is a function of frequency, permeability of the conductor, and resistivity of the conductor. To sum it up, at high enough frequencies, the plating may become the dominant conductor. Good luck, Frank ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################