Adco contour-fit is a semi-custom fit rv cover and is avaialble for most rv models and sizes. choose from sfs aquashed and tyvek fabrics for all-weather protection. adco covers are water-repellent and breathable, this helps prevent mold and mildew from forming while shielding your rv from rain, snow and uv damage.. Free shipping on the best class a rv covers for northern & rainy climates. sizes fit 25-foot to 43-foot motorhomes. beads water off, zippered doors for easy access, lots of built-in features, & super easy to install.. Adco