About Koso M-Mac International, Inc/Pacific Seismic Products, Inc
Today Pacific Seismic Products is the world's leading supplier of earthquake-activated automatic gas shut-off valves and other seismic devices.
Pacific Seismic 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 from 3/4" to 8".
Having a complete hi-tech on-site manufacturing facility in Lancaster, CA, PSP is able to engineer, die-cast, sand cast, CNC machine and assemble their own parts and valves.
Pacific Seismic Products state-of-the-art quality control process leads the industry with high-tech, multi-stage testing of every valve manufactured, assuring you absolute reliability in a "Made In America" product.