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# NIST-4 Watt Balance

## Appears In

                        - Universe’s Constants Now Known with Sufficient Certainty to Completely Redefine the International System of Units
                        - Scientific and Technical Research and Services

Through its measurements of Planck’s constant, a quantity at the heart of quantum physics, the NIST-4 watt balance is contributing to an international effort to define all base measurement units in terms of fundamental constants of nature.

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