A synthetic fence, plastic fence or (when made of vinyl) vinyl or PVC fence is a fence made using synthetic plastics, such as vinyl (PVC), polypropylene, nylon, polythene (polyethylene) or from various recycled plastics. Synthetic fencing was first introduced to the agricultural industry in the 1980s as a low cost/durable solution for long lasting horse fencing. Now, synthetic fencing is used for agricultural fencing, horse racing and residential use. Synthetic fence is generally available preformed, in a wide variety of styles. It tends to be easy to clean, resists weathering and has low maintenance requirements. However, it also can be more expensive than comparable materials, and cheaper products can be less sturdy than more traditional fence materials. Some types may become brittle, faded or degrade in quality after long exposure to extreme hot or cold conditions. Synthetic fence posts are placed into pre-dug holes, or sometimes the synthetic post is fitted over a pre-set post of wood, rebar, or pipe for additional sturdiness. Rails or pickets are inserted into specifically designed slots and grooves within the rails.