PEX

Pex can refer to...peer exchange, a method to gather peers for BitTorrentPEX, the common name for cross-linked high-density polyethylenePEX, in programming - the "PHIGS Extension to X".
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Cross-linked polyethylene, commonly abbreviated PEX or XLPE, is a form of polyethylene with cross-links. It is formed into tubing, and is used predominantly in hydronic radiant heating systems, domestic water piping and insulation for high tension electrical cables. It is also used for natural gas and offshore oil applications, chemical transportation, and transportation of sewage and slurries. Recently, it has become a viable alternative to polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC) or copper pipe for use as residential water pipes. PEX tubing ranges in size from 1/4" to 4", but 1/2", 3/4", and 1" are by far the most widely used.[1]
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(PHIGS Extension to X) Extension to the X Window System providing 3d graphics support.

Airport Name: Paynesville Municipal Airport
Airport Location: Paynesville, Minnesota, United States
IATA Code: PEX
ICAO Code: KPEX