Made of high strength cast iron with a chrome-plated, pressure balanced spool. These valves are interchangeable with Gresen selector valves. 6 port double selector valve diverts two flows in either of two separate circuits. Enables you to run two cylinders with one value. 3000 PSI. U.S.A. Port Size in. 3/4, Max. Flow GPM 40, Max. PSI 3,000, Material Type Cast Iron.