The sign you mentioned is known as "Slope." In German traffic regulations, this sign indicates that you are approaching a steep slope. Drivers should exercise caution as the road may descend steeply, potentially leading to decreased control over the vehicle. It is important to reduce speed and be prepared for sudden changes in traction and braking performance, especially in wet or slippery conditions. Always be alert for pedestrians or cyclists on such slopes, and maintain a safe distance from vehicles ahead of you.