Tin is 2.7" wide and 0.9" tall. Aluminum screw-top stays sealed in any bag.
Powder. Not a liquid. Goes in your carry-on without question.
Aluminum tin and screw-top lid handle airplane pressure changes and rough handling.
Toss it in the bag and forget about it. Still good 5 years later.
The hotel-bathroom shave is when nicks happen most. Different mirror angle, different light, sometimes a dull blade. Tin saves the day.