Proco Products, Inc. has been supplying water and wastewater treatment plants with cost-effective, durable rubber check valves for decades. Our experience in these industries over the years has allowed us to develop sturdy, high-quality expansion joints and rubber duckbill check valves to assist in the control of back pressures while resisting corrosion and breakage from harsh conditions. Proco operates worldwide, and maintains one of the largest product inventories in North America. For more information on expansion joints and rubber duckbill check valves from Proco Products, Inc. and to check pricing and availability, contact us today. For an interactive PDF Applications Form, click here to download.