Matchbox Penetration

This is impossible!  Drive them to their curiosity limits with this one!

You show a matchbox and a long needle with a ribbon passing through the eye of the needle.  After pointing out that the matchbox has a small hole in the center of its face, you push the needle into the hole and through the opposite side of the box.  The needle is pulled through the box and the ribbon is seen clearly threaded through it, passing through both sides.  Your friend can even pull the ribbon out of the box.  Nothing curious yet.  Until what comes next!  You show that the impossible has just occurred when you pull the matchbox drawer open and show what is inside… a solid brass block that completely fills the entire inside of the box.  You drop the block into your friends hand.  They hold a heavy, solid brass block without any holes in it!  Everything can be inspected!