From the Manufacturer Kotap poly tarps have been for more than 30 years. Kotap tarps are of woven and clothed polyethylene that is tear and UV repellent. They are also and mildew repellent and will not rot nor shrink. Product Description symmetrical , light-weight, all purpose -LRB- 5-mil -RRB- tarpaulins are nonesuch for : construction jobsites, roofing, painting, leaf/debris cleanup, camping, picnicking, hunting, canopy and tent fly. They are capture for equipment, boat, exterior furniture, wood piles, or almost anything that needs protection for the weather elements.