30X40 truck tarp is comprised using durable 6 oz., 12 mil poly materials and is resistant to rot, mold and mildew. Each truck tarp includes grommets every 18" and heavy-duty metal D-rings for securing purposes. As with all poly material, the truck tarp is 100% waterproof and can be used all year round (NOTE) SHIPS TIME IS 4 TO 5 BUSINESS DAYS JGTARPSANDCANOPIES