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FACTSHEET | May 11, 2016

MK 20 MOD 0 Improved Flash Bang Grenade

What Is It?

The MK 20 MOD 0 Improved Flash-Bang Grenade, or MK 20 for short, is a safer, more effective, hand-employed flash-bang grenade with greater light output and duration of flash incapacitation than existing fielded flash-bang grenades.

How Does It Work?

The MK 20 works by initiating and ejecting a metal powder payload that reacts with oxygen in the air to create a bright, longer duration flash and bang. The objective is to temporarily suppress the target(s) with improved safety to the user and persons in the target area. The grenade is used as a counter-personnel tool to move people, deny access, and suppress individuals in breaching and/or other non-lethal force operations.

Performance and Safety Testing

The grenade was extensively tested for both technical performance and safety standards during the Testing and Evaluation phase of development. All technical performance measures were tested to a strict confidence and reliability standard, with the grenade meeting all requirements. Strict safety testing was also performed and reviewed by the appropriate review panels.

Human Effects Safety

The Human Effects Center of Excellence at Joint Base San Antonio, Texas, is a source within the Department of Defense for non-lethal human effects expertise. The center performed a thorough analysis of the grenade’s human effects data from developmental testing.  A Human Effects Review Board review was conducted in August 2014, which concurred with the center’s assessment of human effects safety.

System Evolution

The program began in 2007. The current prototype represents Increment III in the development of the Special Operations Flash-Bang Grenade, of interest to and supported by the other Services. The project has completed and the grenade is currently in the production and fielding phase.

Organizations Involved

The following organizations are involved in the program:

  • Department of Defense
    - SOCOM (Lead Service)
    - U.S. Air Force
    - U.S. Marine Corps
  • Department of Homeland Security
    - U.S. Coast Guard