Roundabout Ahead Post Mounted Sign - Diagram 510 R2/RA2 (Face Only)The Roundabout Ahead sign diagram warns of an upcoming roundabout on the current road. This warning sign should be installed where the current junction is about to meet a roundabout. It should not be used for warning of gyratory systems or where the approach to a roundabout is controlled by signals. This may be used with a 572 supplementary plate indicating the distance from the roundabout or with the text Adverse Camber. Refer to TSRGD Traffic