This use is an essential aspect of many industries, but there are hundreds of thousands of miles of crucial pipelines that transport media from its source to the place where it will be transformed into its final product. This media could include piping for crude oil and gas, both onshore and offshore. Valves are used to optimize the pipeline operating conditions, and can be found in the upstream, midstream and downstream section of the piping. Upstream starts at the bottom of the hole in the ground and covers everything on the wellhead up to the choke. In this case, the choke is a specialized globe valve that is mounted on the wellhead to regulate the output of the well. Midstream starts at the output of the choke and ends at the fence of the final destination (usually a refinery). Downstream is everything inside the area of the destination. The most important factor to consider when selecting a valve for a pipeline application is whether the valve is piggable – that is, the inside is designed to be cleaned or inspected.