PLEASE NOTE - I sold this as new and sealed to someone, who had to return it stating it does not appear to be charging.  Not sure if he was doing something wrong, or what.  I do not fully understand this product either.  I tried to test it myself, but could not figure it out either.  Maybe it works perfectly fine.  Simply selling "as is" for parts with NO RETURNS.  I have discounted to simply sell quickly.  Thank you.