This 1.6 oz. tool, manufactured by the makers of the previously-reviewed Utili-Key, can fit on a key chain or in a coin purse, which is where I keep mine. I most often use it for tightening the tiny screws on my glasses, but the small #1 Phillips and flat, pliers, wire cutter/stripper, sheet shear and rule markings (bonus!) are all unbelievably useful at the frequent odd moments you need the right tool which is anywhere but near (particularly the pliers). I have yet to try to go through airport security with it, but the TSA says pliers/screwdrivers and “tools” less than 7 inches can be carried on.