RV Roof Vent Cap 155mm Air Exchange Oxidation Resistant Round Mushroom Ventilation Cap with Mesh Screen for Campervan Yacht Item Type: RV Mushroom Ventilation Cap Size: Approx. 75 x 155mm / 2.95 x 6.10in Installation Hole Size: Approx. 118mm / 4.65in Installation Thickness: Approx. 14mm / 0.55in Application: Suitable for RVs, campervans, motorhomes, yachts, bathrooms, kitchens, warehouses, lounges. It can quickly exchange indoor and outdoor air, providing refreshing air for the interior of your vehicle. If there is water leakage or local damage to the roof of your vehicle, this vent can be used as a patch to repair the damaged area, providing ventilation conditions for the interior of the vehicle while fixing the leakage. Installation Steps: 1. Confirm the position where the hole needs to be opened, clean and open a circular hole with a diameter of 118mm on the panel. 2. Insert the vent cap into the hole and apply water resistant glue around the vent. 3. Secure the vent cap with screws to complete the installation.