The 1482E Standard Inductor is an accurate, highly stable standard of self inductance for use as a low-frequency reference or working standard in the laboratory.
Records extending over 13 years, including those of inductors that traveled to national laboratories in several countries for calibration, show long-term stabilities well within ±0.01%.
It is a uniformly wound toroid on a ceramic core.
It has a negligible external magnetic field and hence essentially no pickup from external fields.