This document discusses the Trident II D5 ballistic missile and the evolution of US nuclear-powered submarines and their ballistic missiles. It provides statistics on the key ballistic missile systems deployed on US submarines since the early Cold War era, including their range, size, weight and launch platforms. The Trident II D5, in service since 1989, is the largest, heaviest and most advanced, capable of carrying multiple independently targetable warheads. It has achieved over 148 successful test launches as of 2013.