English: One of six temporary prototypes made in 1793 by the French Temporary Commission on Weights and Measures of the proposed mass standard for the new French system of weights and measures, the Metric System. Originally called the "Grave", the name was changed to "kilogram" in 1795. Therefore this is one of the first kilogram standards. The prototype is in the collection of the NIST Museum, US National Institute of Standards and Technology, Bethesda, Maryland, USA