For security features we talk about:
Stitch low pressure
Folios patrols or folios elements, both provided with a hologram
Pearlescent strips or optically variables colors
Fluorescent printing inks and fluorescent fibres in the paper
Infrared characteristic feature
These characteristic features must not have been applied with every bank note at the same moment,
it often depends also on the value (purchasing power) of the bank note, because the application also causes expenses.
Only once I wanted to have named all different security characteristic features.