Dead Hand, also known as Perimeter (Russian: Система «Периметр», romanized: Sistema "Perimetr", lit. '"Perimeter" System', with the GRAU Index 15E601, Cyrillic: 15Э601),[1] is a Cold War–era automatic or semi-automatic nuclear weapons control system (similar in concept to the American AN/DRC-8 Emergency Rocket Communications System) that was constructed by the Soviet Union.[2] The system remains in use in the post-Soviet Russian Federation.[3][4] An example of fail-deadly and mutual assured destruction deterrence, it can initiate the launch of the Russian intercontinental ballistic missiles (ICBMs) by sending a pre-entered highest-authority order from the General Staff of the Armed Forces, Strategic Missile Force Management to command posts and individual silos if a nuclear strike is detected by seismic, light, radioactivity, and pressure sensors even with the commanding elements fully destroyed. By most accounts, it is normally switched off and is supposed to be activated during times of crisis; however, as of 2009[update], it was said to remain fully functional and able to serve its purpose when needed.[5][6] Accounts differ on whether the system, once activated by the country's leadership, will launch missiles fully automatic or if there is still a human approval process involved, with newer sources suggesting the latter.