21' Limited Add-A-Room Fits most straight-sided RVs with awning rail to ground dimension of 100" to 138" All features of other rooms plus 1000 denier vinyl fabric, privacy panels that zip together, heavy-duty YKK zippers and Universal Side Panels with twist fasteners Includes 35" tall skirting with sliding eyelets for flexibility in attachment points Sturdy side panel support rafters with brackets providing better, stronger, seal One Year Limited Warranty 100% parts and freight