The Vanguard-class submarines are a class of nuclear-powered ballistic missile submarines operated by the Royal Navy of the United Kingdom. They were designed to carry and launch the Trident II (D5) ballistic missiles, which serve as a key component of the UK's nuclear deterrent strategy. Each submarine can carry up to 16 missiles and is equipped with advanced stealth technology to minimize detection. Commissioned in the 1990s, the Vanguard-class submarines are 150 meters long and can operate at depths of over 300 meters. They are designed for long-range patrols and can remain submerged for extended periods, ensuring a continuous at-sea deterrent. The class includes four submarines: HMS Vanguard, HMS Victorious, HMS Vigilant, and HMS Vengeance.