High-grade stainless steel knob and wire reference weights in class "E0" - with a higher accuracy than OIML class E1 weights - enable calibration of mass standards with the highest metrological performance.
It is commonly called an E0 class, but in reality it is an E1 weight with a lower uncertainty and a maximum permissible error of 1/5, compared to a standard E1 weight.
No, the calibration of an E0 weight is performed at a national metrology institute, either PTB in Germany or METAS in Switzerland.
We have single weight from 1mg - 50Kg and different weight sets. Check our portfolio of calibration weights.
Reference weights are used by national metrology institutes to calibrate other weights (for example of their customers).