The first edition of this book ("The AMAZING 2000-Hour Flashlight") contained 54 illustrations. This edition ("The NEW 2000-Hour Flashlight") contains 128 illustrations. The first edition showed how to modify one flashlight, a specific Eveready model, such that it ran 2000 hours on one battery. Unfortunately, Eveready has replaced that particular light with newer models. This edition shows how to obtain extended run times using other brands - one of which runs 2200 hours, better than the original. (Incidentally, 2200 hours equates to three months of continuous running, night and day.) In general, the modifications or "hacks" are accomplished by adding a resistor (30 cents) to a $5 flashlight. Simplicity is the watchword. Wire glue (a glue containing carbon that conducts electricity) can be used in place of solder. Wire glue eliminates soldering and reduces the task from a techie project to Junior High School level. What with floods, hurricanes, tornadoes, tsunamis, typhoons, earthquakes, blizzards, and downed power lines, there's always a blackout somewhere. If people in general knew the information in this book, life would be a lot easier for a lot of folks.