R-300
Minimum separation distance
No driving without keeping a distance from the vehicle ahead equal to or greater than the one shown on the sign, except when passing. If shown without a distance in meters, it serves as a general reminder of the safe following distance between vehicles set out in Article 54 of the General Traffic Regulations.
Category: Other prohibition and restriction signs
Source: General Traffic Regulations (RD 1428/2003), Annex I; designs per the official sign catalog (RD 465/2025)