I can not comprehend this myself but it is a good thing that we have choices! I also have my Streamlights set for single mode though as the Streamlight interface is tough for me too,I just don't get the timing somehow? Also worth mentioning that the Malkoff MD interface is for me even worse! I have tried carrying Olight as my backup EDC but in the end they seem to always turn on in pocket and try to singe my Junk somehow!?!?!? Not a good feeling.