**Sight is designed to work on same plane rail systems only. Will not work with a railed gas block that is higher or lower than the receiver.
Please don't be one of those people who wonder if they need iron sights on their AR-15. The real question is do I need optics. The real answer is most people don't need optics. They want them. However, unless you shoot long-range, you must run AR-15 iron sights. The only question is which ones?
At one end of the spectrum, there are, believe it or not, AR-15 sights made out of polymer. That's a fancy word for plastic. Don't get me wrong. Polymer is a wonderful material for scales or AR-15 furniture, but for sights? Would you bet your life on it? What would I bet my life on? Scalarworks iron sights, well, they're not really made out of iron. That terminology is a hold-over from the last century. Scalarworks iron sights are really made out of 7075 T6 aluminum. This material is lighter and far superior in strength than anything else available in the AR-15 iron sights world.
In no way am I saying you should never run optics on your AR-15, or any weapon. I am saying you shouldn't depend on them. You have heard the saying that anything that can go wrong will go wrong. The fewer things you leave to chance, the better off you will be. If the majority of your shooting is CQ, then you only need a good set of AR-15 iron sights. Fully adjustable, Scalarworks iron sights are fixed and solidly clamped to your Pic rail. They don't fog up, and there's no battery to fail. Increase your chances to win, opt for the Scalarworks fixed AR-15 sights.