The GBU-43/B Massive Ordnance Air Blast weapon, colloquially known as the “Mother of All Bombs” is the largest conventional weapon in the U.S. military’s arsenal. The MOAB was used for the first time in combat on April 13, striking a network of ISIS-controlled tunnels, caves, and buildings near Achin Afghanistan. The MOAB is a thermobaric device that kills with a super-heated wall of pressurized gasses and is primarily used as a psychological weapon to shock and terrify opposing forces with its massive explosive power, equal to 18,500 pounds of TNT.