Environmental Friendly Use Period - Used with the China RoHs data. Refers to the period during which the toxic or hazardous substances or elements contained in electronic information products will not leak or mutate under normal operating conditions so that the use of such electronic information products does not result in any severe environmental pollution, bodily injury, or damage to any assets. The "e" represents Environmental Friendly Part with the toxic or hazardous substance contained in all of the homogeneous materials is below the limit requirement in SJ/T11363-2006.