[Size] - The RV trailer camper round air vent outside dimensions of the threaded end is 70mm/2.75 inch, the duct connector is 48mm/1.88 inch. As the size picture shows. [Material] - Made of high quality of ABS plastic, black air outlet. Brand new and easy installation. Mesh inside to keep unknown objects out. [Easy to Clean] - The exterior wall air vent hood is very easy to clean, it only needs to be wiped with a wet duster cloth. [Wide Application] - Universal fits marine, boat, yacht, bus, RV for air conditioning air vent ventilation outlet. Low Noise, gives you a quiet space. [Ideal Vent] - Ideal for all tumble dryer vent pipes/hoses, bathroom vents & extractors, air conditioning units, kitchen fans & vents, all home wall vents, heat transfer and ventilation systems, gas & electric dryers, cooker hood extractors, as well as a wide variety of industrial uses.