Brass ball valves work at  600 psi in 1/4″ thru 2″, and work at 400 psi in 3″ and 4″ sizes.  Brass ball valves are stocked up to 4″ in both locations.   High pressure steel ball valves are also stocked in both locations in 1/4″ thru 1 1/4″.  The high pressure steel ball valves work at 5,000 psi or more.  If you need stainless steel or 3-way ball valves, check valves, or anything similar, please inquire and we can special order any of these items for you.