A very nice and early Kadar-era Hungarian People's Republic MHK badge here. Significantly smaller than the pre-1956 models. An attractive badge with multi-colored enamel and a working pin and catch to the reverse. 
 
The MHK was the Hungarian equivalent to the Soviet  "Ready for Labour and Defense" athletic program. The name of the organization is "Munkára, harcra kész" which translates directly to "Ready to work, to fight." MHK existed from 1949 to the mid 1960's.