Good replacement This airflow vent cover is suitable for yachts, RV interior space, suitable for 3inch to 4inch pipes. Easy to install Self-contained locking device, no need to install any fasteners. Premium Material Airflow Vent Cover is made of 316 stainless steel, Stainless steel plus anti-corrosion treatment, durable anti-rust. Scope of SuitableMarine Vent Cover is suit for RV /Camper/boat/yacht/Sailing boat/marine/stairs.t Colour:silver Material:316 stainless steel size:3 inch The actual product may have slight color difference or difference, which will not affect the use Package Contents: 4 * Boats Airflow Vent Cover Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.