The traffic sign you referred to is called "Lane sign - no oncoming traffic with integrated sign 275 3-lane in the direction of travel." This sign indicates that there is a designated lane for vehicles traveling in the specified direction, and there will be no oncoming traffic in that lane.

Typically, this sign is used on roads where a central barrier separates traffic moving in opposite directions, allowing for three lanes of traffic heading in a single direction while preventing any vehicles from coming from the opposite side. This helps enhance safety by reducing the risk of head-on collisions in areas where multiple lanes are operational.

Drivers should ensure they stay in their designated lane and be aware that this specific lane arrangement is designed to facilitate smooth traffic flow in the permitted direction without the concern of oncoming vehicles.