If you have an older versions of the Full NIST Mass Spectral Database, select this product to upgrade your license to NIST 20.
The latest release of the NIST Mass Spectral Library, which includes the NIST Tandem Mass Spectral Library and NIST/EPA/NIH Mass Spectral Library and NIST GC Retention Index Database greatly increases the number of compounds and spectra since the 2017 version.
NIST Tandem Mass Spectral Library, 2020 release
NIST/EPA/NIH EI-MS Library, 2020 release