Maass Midwest introduced the industry’s first original tapered seat valves for VFD pumps. The model 531, 529 and 529 XLT provide 40 to 60 percent greater flow than the industry standard. The unique seating poppet design insures long life and reliability. The valves matching Celcon poppet and guide makes for a smooth quiet operation. All are enclosed in a no-lead brass body featuring wrenching lugs. The models, rated at 180 degrees, are also excellent for hot-water systems.