This is without a doubt the most concealable handgun ever!
Here is a man OC'ing it:
It is the world’s smallest working gun that does not exceed 5.5 cm in length. It can shoot 2.34mm caliber rim fire ammunition making this the smallest rim fire ammunition in the world. If you thought that this pistol is only for show, then lemme tell you that this double action revolver has all the features found on a real size gun. It can fire real bullets at 270 mph which can be deadly in close shooting range.The gun weighs only 19.8 grams or 0.7 oz and fires live and blank ammunition.
I think this may be a great defensive option for those people who need ultra concealment and don't need those overkill large caliber bullets. After all it's shot placement that matters not caliber right?