The MARS-H brings LMT’s innovative design of their MARS-L to the MWS platform. The LMT Modular Ambidextrous Rifle System (MARS) lower receiver offers ambidextrous controls to include: selector, magazine release and bolt catch and release. The ambidextrous magazine and bolt catch mechanisms are machined directly into the receiver and are very intuitive. This lower receiver is designed with several unique LMT features to further enhance its durability and versatility. These features include: enhanced magazine well, two-stage trigger group, winter trigger guard, ergo grip, and QD endplate. LMT MWS lower receivers are only guaranteed compatible with LMT upper receivers. Other brands may not fit or function correctly.