Ontario, Calif.-based Vertex Water Products announces that the Pure WaterMachine reverse osmosis system has completed the WQA Gold Seal Certification to ANSI/NSF Standard 58. The system models PT-4.0 four-stage, PT-4.0/P four-stage with booster pump, and the PT-4.0/5 P with booster pump are on the approved list for chemical extraction, structural integrity and certified reduced contaminants. The company assembles RO filter systems for home and commercial use up to 6,000 gpd ratings.