In reply to deepstar:
We used to take our T4 through on that ticket. There are two classes of light vehicles - class 1 up to 2m high, and class 2 over 2m. The ticket is for class 1. However, the Italian autoroutes are more expensive for the van than a car - they have different definitions, I think. Also, as I remember, the Grand St Bernard tunnel costs more for a van.