I Brought this Item this afternoon and on the box it stated "60 run time" and "4 hour charge".I purchased the item based on this information. After opening opening the razor I read "The battery should be charged for 16 hours, and this will provide 40 minutes of shaving time." Please explain to me why the outside of the box exaggerates the information on the instruction manual. I have attached a pic of both box and instruction manual.