Quick view TacFire Tacfire Clamp On, Tacfire Mar001-co .750 Clamp On Lp Gas Block $12.51 Tacfire's clamp on low profile gas block is cnc machined from steel with a erosion resistant parkerized finish.It replaces the an existing a2 front sight and is compatible with 5.56/223 rifle with.705" barrel diameter.A roll pin, screw set and hex wrench... Compare Add to Cart