A MS1 central reservation signal that is displaying a traffic must leave motorway at the next exit. This is the alternate aspect used for this message, with the arrow pointing to the right in this version, which is the opposite side of the roadway from normal motorway slip road placement.
The amber lamps flash in pairs from top to bottom.
This vector image includes elements that have been taken or adapted from this file:
Adapted from Mauls.

UK Government