The B&T GHM9 series is a line of cost-effective, competition-oriented SMGs in SBR and pistol configurations. It is available in 9mm caliber and includes a few variants produced in 2 generations, sharing some features but also having some differences. Compared to the first generation, GHM9 Gen2 features improved ergonomics and some modularity and functionality upgrades. The GHM9 was named after the Grasshopper Mouse, a small rodent inhabiting the Southwest United States famous for eating Scorpios while being immune to their venom. The GHM9 is inspired by the successful B&T APC9 while being more flexible and modular. The B&T GHM9 was designed for self-defense, home defense, target practice, competitive shooting, and professional use. The main qualities of the GHM9 are quality build, modularity, and easy handling. The series includes models such as the GHM9 C, GHM9 G, and GHM9 CG in a carbine and pistol configuration and the GHM9 SD and GHM9 SD G in the pistol versions. The GHM9 G models feature a 6.9-inch barrel, while compact models (GHM9 C and GHM9 CG) have smaller, 4.3-inch barrels. The GHM SD models feature a pre-installed suppressor and a 5.7-inch barrel. The GHM9 G models feature a Glock lower, while all models will work with APC9 Pro lower receivers. A high level of modularity in the GHM9 series allows for easy switching between barrel lengths, easy handguard and stock changing, and easy suppressor installation. The GHM9s are compatible with Glock, SIG P320, and proprietary B&T magazines by switching the lower receiver group. Other standard features include a telescopic stock for SBR versions, backup sights, accessory rails, a B&T recoil-reducing buffer system, and a standard 30-round magazine, or a 33-rd Glock magazine.