Nikon Z fc N2016 Reference Manual page 254

Fine-tuning preset manual white balance
D
The selected preset can be fine-tuned by selecting [Fine-tune] in the preset
manual white balance menu (0249).
"Edit comment"
D
To enter a descriptive comment of up to 36 characters for the current white-
balance preset, select [Edit comment] in the preset manual white balance
menu.
"Protect"
D
To protect the current white-balance preset, select [Protect] in the preset
manual white balance menu. Highlight [On] and press J; the current white
balance preset is now protected. Protected presets cannot be modified.
C The photo shooting menu: Shooting options
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