AWS with Suppressor

This is an "Automatic Warning System", or AWS for short. From right to left:

Ramp - to ensure nothing hanging from a train will damage the unit;

Permanent Magnet (with a collection of iron filings generated by train brakes)

Cable terminate section (for the Electo-magnet)

Electro-Magnet (energised when the signal it applies to is at green).

Done