The DS-15 M4 Assembled Fixed Magazine Lower is a complete fixed magazine AR-15 lower built around Dark Storm Industries' patented receiver design. Manufactured without a magazine release and equipped with a permanently affixed 10-round magazine, it provides a ready-to-use foundation for building a fixed magazine DS-15 while retaining familiar AR-15 ergonomics and component compatibility.

Machined from forged 7075 aluminum and finished with Mil-Spec Type III hardcoat anodizing, the lower arrives fully assembled with M4 furniture, a single-stage trigger, safety selector, DSI Mil+ carbine buffer system, and extended takedown and pivot pins.