I've have 7 ot 8 "tactical" flashlights and replacing all those 123 batteries sure does get spendy.
I've started using these new Mag Light flashlights.
The xl 50 has a end cap that turns it off on, strobe & two output settings.
The xl 100 end cap is very cool, it is motion activated with 5 or so settings.
They both take 3 aaa batteries.