The term "6 MPm" associated with a counterblow hammer appears to be part of a model number rather than a standard capacity measurement. There is confusion regarding its meaning, with some suggesting it could represent "MegaPond-metre," akin to the energy measurement of kgm. The discussion highlights two different specifications for energy delivered by the hammer: an impact energy of 1470 kJ and a full blow energy of 7000 kgm. Despite various searches, clarity on the exact definition of "MPm" remains elusive. Further investigation into specific models may provide additional insights.