The 3 levels are primary, secondary and level 16 (which is the lowest I think). You can preset the primary and secondary to any of the 16 available levels of the ARC4 you want. I think primary is set to 1 (the brightest) by default. I set mine to 4 on primary and 7 on secondary. Together with the lowest level that gives three nicely spaced out levels. The run time is also much increased on level 4, which is still nice and bright. If you want full power just hold the button down. There was a thread about what people set there levels to a while ago in the arc forum. Refer to the FAQ for setting level brightness. Any questions drop me a PM. Great light. Enjoy. /ubbthreads/images/graemlins/cool.gif