Sig Sauer 5.56mm Flash Hider, 3 Prong. Made from steel with a black finish, this three prong flash hider is designed to fit Sig Sauer M400, SIG516 and MCX rifles chambered in 5.56 NATO and .223 Remington and will also fit most standard AR rifles. The flash hider is threaded 1/2" x 28 TPI. Made to the highest Sig Sauer standards in material and workmanship. From the world leader in firearms genuine Sig Sauer parts are designed around the same relentless standards put into every pistol and rifle they make. Kit up, dress up, or replace your original parts with nothing but genuine parts from Sig Sauer.