Being the successor of the DM2A3, it features an advanced electrical propulsion system and a fiber-optic cable for torpedo guidance and communication, which, in conjunction with advanced signals processing and mission logic, makes the torpedo largely countermeasure resistant.
[5] With a fully digital system architecture, increased range and speed and its new conformal array sonar with a very wide panoramic sensor angle as well as the additional wake homing sensor, the DM2A4/SeaHake mod 4 provides greatly advanced performance over its predecessor.
The homing head shell is a hydrodynamic optimised parabolic shape which aims to reduce torpedo self-noise and cavitation to an absolute minimum.
[2] The weapon has a modular design that includes 2–4 silver-zinc oxide battery modules and is able to achieve a range of more than 50 km (27 nmi) and a speed exceeding 92.6 km/h (50 kn) powered by a high frequency permanent magnet motor, with a closed-loop cooling system independent from the environment.
[10] In October 2020, DM2A4 was chosen as the preferred solution, with a program consisting of 36 DM2A4, plus refurbish of number of older SUT Mod0 to Mod4 standard, plus extra batteries for older SST torpedoes / SUT Mod0 torpedoes, with a total cost of 105m euro.