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Pacific Seismic Products (PSP) is the world's leading supplier of earthquake-activated automatic gas shut-off valves and other seismic devices. 

PSP was incorporated in 1989 when it acquired the rights to Koso's seismic valves. PSP has continued to develop its gas shut- off valves by adding vertical and specialized types to its already successful horizontal line, giving PSP the most complete line of seismically-activated gas shut-off valves in sizes ranging from 3/4" to 8".

Having a complete hi-tech on-site manufacturing facility in Lancaster, California, PSP is able to engineer, die cast, sand cast, CNC machine, and assemble their own parts for its products.

A state-of-the-art quality control process leads the industry with high-tech, multi-stage testing of every valve manufactured, assuring you absolute reliability from a "Made-in-America" product.

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