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 7075-T6 just like Sharps lower receivers.  Anodized black.  Comes with forward assist kit installed. Designed to not use a Dust Cover.

• Made from billet 7075-T6 aluminum
• Mil-Spec Type III hard coat anodize with additional interior lubricity coating
• Engraved 'SHARPS BROS.' on both sides
• Weight: 9 oz