The AM-15 Stripped Lower Receiver is American made with superior quality for less! CNC machined from a high-strength, 7075 T6 aluminum forging for reliable performance and outstanding durability. Machined to Military Specifications & Standards and marked "MULTI-CAL" to be used with multiple calibers on the AR-15 platform. This Lower Receiver comes in type III black hard anodizing with a closed trigger guard.