No Overtaking Post Mounted Sign - Dia 632 R2/RA2 (Face Only)The no overtaking sign diagram 632 prohibits overtaking on a length of road where double white lines cant be or are not used. The restriction of overtaking should usually be done through the use of double white lines where possible, and this sign should not be used where double white lines are already in use. You may need a no passing sign in situations where: The road is less than 6. 1m wide, making double white lines impracticable (chapter 5 of the