Troy's M4 Front Folding BattleSight is durable, accurate, and requires no tools for adjustments. Easily installed and deployed, the sight can be moved or taken off without permanent modification to the firearm. A stainless-steel cross-locking system ensures the sight remains upright and zeroed under extreme combat conditions. Sight can be securely folded away with the push of a button. Each click adjusts .50 MOA.