M5 and M2 technologies are used for 600V, 650V, and 700V. M5 is the technology that is in position for hard switching applications such as high power PFC or full-bridge. M2, or the newer M2 EP devices target resonant topologies in which ST performs as well as or better than the competition. The M2 devices are Zener diode protected against ESD spikes, and range from 400V to 700V. M2 devices can also be used for hard switching. In the case that an application requires a fast recovery diode, ST has a variation of the M2 technology that is called the DM2, targeting phase shifted full bridge. For very high voltages STMicroelectronics produces a technology called K5 which is capable from 800V to 1500V . At this time this is the only very high voltage super-junction technology on the market. A competitor has a device in this market called the C3, which is 15 years old. It features lower performance than the K5 in terms of RDS(on) times gate charge.