Accepts all accessories designed for the M1913 Picatinny rail system. The folks at Troy design and manufacture technically superior products that perform in the most extreme combat conditions... ensuring that those who protect and serve the U.S.A. are working with the best. This SIG 556 Battle Rail installs easily with no special tools. Creates the ultimate Sig 556® pistol. Designed to fit Sig 556 receivers with three rail screws. Available in Black and Flat Dark Earth.