A Rigid Medium Goods Vehicle with a trailer is also known as a Rigid up to 7½ tonne with a trailer.
If you need to tow a trailer with your truck, then you need to pass your C1+E. Trucks that are heavier than 3.5 tonne but less than 7.5 tonne are C1 Vehicles - to drive these vehicles with a trailer you need a C1+E licence.
Civil engineers towing mini diggers or mini excavators; Arboreal Specialists and Tree Surgeons towing chippers and mulchers; Recovery Vehicle drivers and Recreational Vehicles towing leisure craft, cars, motor bikes or boats behind their RV's, may all need the C1+E entitlement.
Once you have obtained your Cat C1 licence you will then be able to apply for your Cat C1+E.