Truma portable fridge/freezers are weather-resistant. This means they are not affected by a little spray water. They are however not designed to be left uncovered outdoors in the rain or to be used in wet conditions. Please also consider that the appliance must not be exposed to rain or other liquids.
The use of an insulating cover and protective cover offers protection against slight water splashes or brief spells of light rain, however a hazard is also then posed by water ingressing into the inside of the appliance through the ventilation slots, which must be avoided at all costs.