På dansk Lyssignal
Traffic signals ahead, often where you cannot see them from far. Ease off the accelerator so a sudden red does not surprise you.
A Triangular with a red border: something ahead needs your attention. Outside built-up areas they normally stand 150-250 m before the hazard, closer inside town.
Drawing from Wikimedia Commons, free of copyright under section 9 of the Danish copyright act. Code and name follow executive order 425 of 13 April 2023 on road marking. Study material, not the legal text.