Keep debris off your slideout roof and out of your RV interior. Made with stain and mildew-resistant vinyl, Dometic Deluxe 228" Polar White SlideToppers shield your slideout roof from water and debris. Featuring a modernized design for clean aesthetics, Dometic SlideToppers are designed with an anti-billow mechanism that prevents the cover from billowing during travel. These complete EZ kits include awning rail and tall mounting hardware and are quicker and easier to install than earlier versions. The "tall" mounting hardware option is particularly used for Dometic's Deluxe and Elite Slide Topper Series. The tall hardware kit offers a 45° mounting clearance. Deluxe SlideToppers offer a weathershield material of black or polar white vinyl wrap and comes in sizes from 60" to 363".Measuring InstructionsMeasure the room edge to edge and add 6", round to next longest even half foot (60", 66", 72", 78" etc.). This product will not work on slide rooms with a full extension of over 42".Includes• Vinyl roller tube assembly• Awning rail• Tall SlideTopper hardware Anti-billow mechanism prevents the cover from billowing during travel Tall mounting hardware is particularly used for Deluxe & Elite Slide Topper Series Tall hardware kit offers a 45° mounting clearance | Dometic Deluxe SlideToppers with Rail and Tall Hardware, 228", Polar White