I am on the fence on this one, it is either a great idea are the worst idea!  It is basically a bolt that you can hide things in.  The size really restricts this product from being useful except for drug addicts hiding their stash.  However it is ingenious as no one will ever find what you put in there.  If you mix it with other bolts you may never find what is hidden in their either. I was based from cold war KGB spy bolts holding Microfilm Check it out via Amazon.