PolyPRO™ 3 RV Class B Cover gray 25-27 ft. Specifically designed for Class B RVs, this cover has a triple-ply PolyPRO 3 top and thick, single-ply sides to protect against rain, snow, dirt, nicks, and scratches for all-season protection. Its integrated air vent system, combined with the quick drying PolyPRO 1 sides reduce wind stress and vent inside moisture. Create a custom fit with adjustable front and rear tensions panels and elasticized hem corners, and reduce the need to crawl under your RV with the integrated rope attachment system and toss bag. Don't worry about having to completely uninstall your cover to access the engine or doors to your RV, as there are zippered panels designed to give you access to these areas! Stuff sacks included.