Four AA batteries, NERF is a product of the famous American toy brand Hasbro. The trademark means "Non-Expanding Recreational Foam" (English: Non-Expanding RecreationalFoam), and the Chinese translation is: Heat , Chinese official website link. In most cases NERF specifically refers to toy launchers made of NERF sponge as the base material. From the structure classification, generally speaking, the cylinder structure is mostly a manual launcher, and the flywheel structure is mostly an electric launcher; from the type classification, it can be roughly divided into soft bullet launchers, cold weapons and water guns, etc.; from the product series classification, including, but Not limited to Elite series, Zombie Attack series, UFO series, MEGA series, Mulan series, DART TAG series, etc.; there are also NERF sea