This is a large enamel and metal pin badge advertising the 1972 ISDT Enduro in former Czechoslovakia and featuring the 6 logo of the event.
The badge face is 5.4cm high and has a safety clasp style fastener to the rear. Historical Background
The ISDE was first held in 1913 at Carlisle, England. It has occurred annually, apart from interruptions due to World War I and World War II, at various locations throughout the world. The early events were a true test of machine, rider skill, and reliability. Held on the 'roads' of that era, today most of the routes are truly 'off road'. Originally titled the International Six Day Trial, since 1980 it has been called the 'ISD Enduro'.
The 1982 event was held in Czechoslovakia and was the 57th such event.
Motokov were one of the Czech race sponsors. Motokov no longer exist, but in the 1960s and 1970s they were the company who regulated vehicle import and export into the country.
You can read all about the Six Day Event here on Wikipedia