Fantastic sights with limits - Griffin Armament M2 Micro Modular Front Sight

For metal sights they are very light and have a very unique design. They work and tighten down really well. Unfortunately the design limits their fitting on some of my uppers. These sights if you look have a rigid base and would not fit one of my F1 uppers and my Spikes upper. They literally would not slide on. They worked fine on my Anderson, LBE, Delton and a different F1 upper. I was concerned that they would twist and turn with the way they bolt down (set screw) into the upper receiver or rail. The set screw will also put a mark in your upper receiver or your rail where it's tightened down. SO pick the right spots the first time. But all said and done I would recommend them.