The 20mm Model 7 Rifle Grenade was the first standardized Rifle Grenade adapted for use with the principle weapon of US Military during World War II, The M1 Garand. First designed and deployed in 1943, The Model 7 would have a long production life, being used until 1957. Designed in various Round configurations, The Model 7 could be used for Anti-Tank operations as well. The Model 7 was a mounted device which was 7-inches long. Easily installed, any Infantryman was capable. Fired using a "Dummy Round", the charge would trigger a Primer Cap, which propelled the Grenade to it's target. The explosive Device could be pre-set or detonate on impact. The maximum effective range was 380-yards. Effective, The Model 7 was used in all Theaters of combat in World War II and saw extensive use in The Korean War of the 1950s.