Flomatic Corporation introduces a new, special patent-pending, full ported submersible pump check valve for use with variable-frequency drive (VFD) control submersible pumps. Standard check valves will “chatter” and be noisy when a VFD goes to low flow, causing premature wear and eventual failure. This unique Model 80DI VFD valve is designed to minimize flow losses at rated flow and hydraulic shocks in the pumping system. An exclusive stainless steel guided poppet system ensures that the valve automatically adjusts noiselessly from high to very low flow rates. Only from Flomatic Valves 1-800-833-2040 www.flomatic.com. Flomatic Corporation.