Belgian road tax

Are there any details on the road tax yet ,it’s for over 3.5 tonne but what about 3.5 tonne towing ?

Found this and I think it means it’s only for vehicles over 3.5t MGW, but if the MGW is over 3.5t then you must declare the train weight of the vehicle. I haven’t applied for a box for our van and that tows a trailer, so I hope I’m right.

-The Gross Vehicle Weight: the kilometer charge is due for trucks of more than 3.5 GVW. When the pulling vehicle has a GVW of more than 3.5 tons, the Gross Combination Weight Rating (GCWR) needs to be declared (trailer included when the truck is equipped with a towbar

Thanks muckles for the link ,looks like they’ve covered every angle .