India is getting ready to test its long range nuclear-capable submarine-launched ballistic missile (SLBM) K-4 from an underwater platform on 31 January. Having a length of 12 metres, K-4 missile weighs around 17 tonnes and is able to carry a two-tonne warhead. Developed by The Defence Research and Development Organisation (DRDO), the missile has a range of 3 thousand 500 km and designed to be launched from a depth of 50 metres.