Here's a lame dame photo, CN 399 screams downhill knocking down the advance signal to Mansewood along Canadian National's Halton Subdivision, the yellow over red flag taped to the signal mast indicates a rule 42 work block up ahead (the red flag is 2 miles away which is the start of the working limits) where trains must call the foreman in charge for permission through their working limits. Another feature added is the directional arrow just below the restricting plate, this feature (when you're lined up) helps train crews on knowing which track they'll be placed on when they come up to the controlled location, when flashing it means you are lined up onto the north track, when not flashing you are lined up the south track.
