The Spike's Micro Gas Block is a high-quality low-profile AR-15 component featuring a .625" bore diameter and durable black nitride coating for superior corrosion resistance.Spike's Micro Gas Block .625" with screwsSolid billet steel construction for maximum durabilityBlack nitride coating for corrosion and wear resistanceLow-profile design for enhanced aestheticsDouble set screw mounting systemCompatible with AR-15 platform riflesEngineered for reliable performance and long-lasting service this micro gas block provides consistent gas regulation while maintaining a sleek streamlined profile on your AR-15 build.