Sig Sauer Elite Performance Match Ammo is designed to bring out the best in today's high-performance AR rifles. Subsonic rounds, ideal for suppressed AR rifles, features Sierra Match King projectiles for superior accuracy, increased downrange terminal performance, and low noise level characteristics. Then there are Supersonic rounds with Sierra Match King projectiles for incredible accuracy and minimal dispersion when suppressed. Features match grade brass cases. Elite Performance Match Ammo functions with mil-spec 5.56 NATO bolts and magazines. Box of 20 rounds.