Advance Clear to Medium · Rule 413

Indication: Proceed, approaching second signal at MEDIUM speed.

1. A high mast, staggered, double aspect signal displaying flashing yellow on the top, green on the bottom.
2. A high mast, inline, double aspect signal displaying flashing yellow on the top, green on the bottom.
3. A high mast, inline, triple aspect signal displaying flashing yellow on the top, green in the middle, red on the bottom.