Perfect for keeping your matches dry in wet environments.
Take 2 shotgun shells
Fold one of the sides in on one of the shells, just make it so it fits into the other.
Push the folded shell into the normal shell to make sure it fits. It is usually really tight at first.
Take the striking side of the match box, I used a mini box, and caught off a strip. I cut off both sides of the mini box because they will both fit.
Put the matches and cardboard strip in the folded shell, and push the other shell on tight and your good to go!