This super-sized PVC floor covering not only provides an extra layer of waterproof protection under your XF2 Bivvy, keeping the sewn-in groundsheet in optimal condition, but it also extends to the entire surface of the XF2 Porch Extension v2, protecting all your valuables, equipment and luggage from contact with the damp ground. Essential for keeping the entire shelter clean and dry, the extra protective layer also helps protect against punctures or damage to the sewn-in bivvy groundsheet. When the porch is not in use, the sturdy but soft material can be folded in half, creating a double-thick base layer under the bivvy for maximum protection.