former 51T6 silos. The new PRS-1M is a modernized variant of the PRS-1 (53T6) and can use nuclear or conventional warheads. It can hit targets at ranges of 350 km and altitudes of 50 km. Gallery See also Main Centre for Missile Attack Warning A-35 anti-ballistic missile system A-235 anti-ballistic missile system Ground-Based Midcourse Defense References External links . . Anti-ballistic missiles of the Soviet Union Anti-ballistic missiles of Russia Missile defense NPO Novator products Military equipment introduced in the 1990s