Released in 1974, the HK91 was developed as a U.S. civilian sales version of Heckler & Koch's venerable G3 select-fire, roller-delayed battle rifle, with a shelf-pattern receiver to prevent the installation of select-fire internals. Manufactured in 1981. Features hooded blade front and four position drum rear sight, birdcage flash hider, textured triangular handguard, finger groove grip with thumb rest, collapsible buttstock, and "S/F" selector. Includes three extra magazines.