I have installed on a ncstar quad rail handguard with a ncstar tactical light. This grip puts my thumb in perfect position to operate the lights pressure cap.
The grip was really loose out of the box. The pivot screw wasn't tight, but once tightened it was pretty solid. I'm very satisfied with this product.
Pros: Works like it says
Cons: A little shaky
This review was written in the old system and had content requirements that are different than reviews written today.