Caliber: 5.56mm - Grain: 55gr - Bullet: Full Metal Jacket - Muzzle Velocity: 3180 fps - 20 Rounds per BoxAmmunition cannot be shipped to a P.O. Box, please use a physical address during checkout. For restricted state buyers (CT, IL, NJ), please email a copy of your state's credentials, and a photo ID along your order number to [email protected] within 5 business days to avoid cancellation and refunding your order. For California, Massachusetts and New York buyers, please have your dealer email us a copy of their FFL or Ammo Vendor License along with your order number to [email protected] within 5 business days to avoid cancellation and refunding your order. Your order will not ship without us receiving this information. Thank you for your cooperation