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IPK housed in nested bell jars

IPK (international prototype kilogram)housed in nested bell jars

The IPK (international prototype kilogram) is housed under three nested glass bell jars with a carefully controlled atmosphere. The IPK was retired on 20 May 2019.

Rights: Image reproduced with permission of the BIPM, which retains full internationally protected copyright (© BIPM)
Published:17 August 2011Size: 190.56 KB