... 4)Double power PC key calculator 12 digits big display auto power off double power Desktop calculator1. parametersItem No.SpecificationMaterial Des ... ,Blister card packing,12 digits,decimal point selection,TAX rate,Auto power off,PC-key computer,Freely adjust Angle,Abdication, double ... supply, this is to lengthen the battery life.When the batteries are without power, solar still can continue to use.6 ...