For the second

Standard frequencies - TITLE

The radiations listed below may be used as secondary representations of the second.

Wavelength ≈ 265 nm

Wavelength ≈ 267 nm

Wavelength ≈ 282 nm

Wavelength ≈ 436 nm

Wavelength ≈ 467 nm

Wavelength ≈ 578 nm

Wavelength ≈ 674 nm

Wavelength ≈ 698 nm

Wavelength ≈ 698 nm

Wavelength ≈ 729 nm