Late model Hickok 539C, Calibrated, Clean, and Has Little Use 
One of the last of the brushed aluminum chassis' with the decorative etching
See pictures 6, 7, 8, and 9 for calibration specs, some additional notes, and relative information for this 539C. Calibration Sticker added after the pictures.
If you want to know anything else please ask. 
You can have this 539C calibrated at no charge within three years of the date of purchase, but will have to pay for the shipping. There may be additional charges if parts are needed,  e.g. new rectifiers  You will receive a calibration card with the date of purchase. 
 
Please see the calibration information in the pictures.
 
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