One kilogram (2.205 pounds) professional hexagonal weight in cast iron and lead, dating from the end of the 19th century. Handling is facilitated by a ring. 
 The lead part was used to adjust the weight and accommodate the weight and measurement control punch.
<a href="//commons.wikimedia.org/wiki/User:Cquoi" title="User:Cquoi">Cquoi</a>
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