If it is for a dad going into the Military ~ like actually going to do a tour somewhere like Afganastan and you are wanting this to be something he could take with him I would opt for the 'black mat style beads' and perhaps instead of a key chain make the 'loop' out of black threading of some kind more like a 'bookmark' style or if you want the key chain loop maybe black leather cording for jewellery making something MATTE verses the shiny colored beads or silver key chain .... you do not want anything that would 'reflect light' on night vision goggles that could give away a position ~ they have very strict guidelines about what they can have on their person and in their camps and so forth.