Plastic lumber made from post-consumer and post-industrial waste (including soda and milk bottles, plastic grocery bags, etc.) is available from many manufacturers. Plastic wood offers several advantages over natural wood. It is generally resistant to rot, mildew and insect infestation, making it desirable for seawalls, docks, and other marine applications. Decks, picnic tables, landscaping ties, benches and refuse containers are also common uses for plastic wood. Some plastic lumber is injected with dyes during the production process, which makes stains and paint unnecessary. Uncolored products can generally be painted. Most plastic wood cannot be used for load-bearing capacity. Like natural wood, plastic wood is subject to expansion and contraction with heat; however, the magnitude of expansion may be much greater than with natural wood and varies from product to product. Most recycled wood products can be cut and shaped with traditional wood working tools, but many manufacturers recommend the use of special fasteners in construction. Since most plastic lumber does not have the same bearing strength as natural wood, it is crucial that manufacturers specifications regarding the distance between supports be followed very carefully.