No Stopping Post Mounted Sign - Diagram 642 R2/RA2 (Face Only)An area on a main carriageway marked by the red cross of diagram 642 means stopping is strictly prohibited due to the speed and design of the road, this sign is otherwise known as the 'Clearway Sign'. The beginning of a clearway must be marked with this sign with a supplementary plate indicating the length in miles (rounded to the nearest whole mile if longer than 3 miles). Signs can be placed on both sides of the road is required. The end of the