Sharps Bros AR15 Upper SBUR03

It matches any of the Sharps Bros. lower receivers perfectly, and it also matches the lines of their handguards perfectly as well. This receiver is meant for .223, 5.56, 300 BLK and 6.5 Grendel calibers.  Port opening is not large enough for 450 Bushmaster, 458 SOCOM or 50 Beowulf.Made from billet 7075-T6 aluminum Mil-Spec Type III hard coat anodize 'SHARPS BROS.' discretely engraved on both sides Manufacturer Part Number: SBUR03