All box cutters [commonly known as Stanley knives] and any other like tool that contains a razor type blade [used to slice] are restricted from carry-on luggage, but they can go in your checked-in luggage.
Items must be in checked-in luggage only
These items can be used as weapons and cause harm to passengers and crews.
You will be asked to relinquish all dangerous or prohibited items found in your carry-on luggage. If you refuse:
AvSec X-ray bags going onto aircraft to ensure there is nothing dangerous in them.
For more information, see Retrieving your removed items.