Building a reliable 9mm AR when using Foxtrot Mike Products. The FM Products FM9 9mm lower receiver is machined from a block of billet 7075-T6 aluminum and is compatible with Mil-Spec components. This dedicated 9mm AR lower is designed to be used with the highly popular Glock magazines and even features a last round bolt hold open which is not a common feature of other 9mm lowers. The AR 9mm lower Glock compatible receiver comes stripped, so you can customize it to your liking. It does, however, come with the proprietary magazine release and bolt release pre-installed. Start your AR-9 build off right with the FM Products 9mm stripped lower receiver.Features: Machined from billet 7075-T6 aluminum Compatible with 9mm Glock style magazines Last round bolt hold open Compatible with Mil-Spec parts and triggers Lifetime warranty through FM Products 100% made in America Not California compliantBecause the AR9 lower is machined directly from billet, it allows FM Products to add features like an integral trigger guard and a magwell designed specifically for 9mm Glock magazines. It gives them the freedom to build a truly unique lower that functions well and looks great doing it.Feature rich, high-quality, and affordable, Foxtrot Mike Products offer cutting edge solutions utilizing the highest quality materials and manufacturing processes available.