The 1417 Four-Terminal Capacitance Standard consists of a 1 uF standard capacitor and two precise inductive voltage dividers used to scale the value of the 1 uF capacitor up to 1 F in decade steps. This arrangement provides accuracy and stability unattainable with very high-value true capacitors.
0.25% basic capacitance accuracy
0.02 to 0.25% ratio accuracy
Dissipation-factor standard