These 'balises' precede mechanical distant signals on lines with lines speeds above 70 km/h. They are placed at 50 m intervals, the final one (with one stripe) at 50m before the distant signal. These panels apply to the period before 1970, when the system was changed to one with fewer panels.
The pack contains panels in clean and slightly faded, dirty versions.
On lines with lower speeds (40 - 70 km/h), caution signals may be absent and panels with 'chevron'-type markings are used preceding the stop signals; they are spaced at much larger distances. These chevron-type warning panels are on the DLS ('Balise 1 chevron' etc.).