This specification covers carbonized nickel strip, carbonized nickel-plated, and nickel clad steel strips for use in electron tubes. The carbonized strips should have a uniform appearance with surfaces free of any lubricant. The firing process used for testing carbon loss should be done in a way that ensures an acceptable standard of quality for operation in electron-tube applications. Test specimens should be protected using a suitable covered boat to prevent radiation from the furnace heating elements or direct gas impingement. After firing, samples should not show any visual carbon loss or exposed uncarbonized bare metal. Unless otherwise specified, each coil or spool should be of continuous length of strip without any kind of joint. Each strip should be coiled so that the normal curvature is not reversed.