These bags are excellent for the packaging and shipping of dry goods because of their superior strength and puncture resistance due to their woven construction. Woven polypropylene bags with attached tie-string, a simple, but effective way to prevent surface scratches or dings on sensitive parts, metal molds, and valves during transport. Puncture and tear-resistant woven bags provide protection from many shipping hazards including protection from ultraviolet rays. Suitable for heavy or oversized parts and supplies. Sandbags are super strong and have 1600 hours of UV protection without disintegrating and make excellent sand-filled flood barriers. These woven cloth shipping bags are often used to protect critical plumbing valves and steam engine parts, hard to replace special order items in transit require something stronger than your typical plastic parts bag. That is where heavy duty woven polypropylene bags come to play. They can safely protect parts that normally would rub and wear right thru a heavy-duty 1-4 Mil poly bag. Bags can also be used as sandbags. Our tough woven polypropylene bags are excellent for use as sandbags in flooded areas and are strong enough for temporary wall, berm, trench and levee construction.