Metal Foil Resistors are high precision resistors made of thin metal on a ceramic substrate. They are extremely accurate and provide excellent resistance stability. They are similar in construction to wirewound resistors but instead of using metal wire, metal foil is used as the resistive element. In metal foil resistors, strips of resistive material such as gold, nickel, or metal alloy, are deposited onto a ceramic substrate in a very tight pattern, resulting in thin metal foils. This thin material provides very high precision and low TCR (temperature coefficient of resistance), very tight tolerances and excellent noise performance. These resistors are used in applications requiring the highest resistance accuracy such as precision instrumentation, calibration and testing and are often used in medical and automotive applications.