I got this to fix up one of 6P lights. The guard around the button is nice but can hinder operation since the button is recessed and not as exposed. Having the click on ability makes any Surefire much more useful. I am in the military and use my 6P a lot, and the cap makes things a little easier.
Pros: Easy to use, added features over stock
Cons: Adds bulk to light
This review was written in the old system and had content requirements that are different than reviews written today.