Series 709 Double Check Valve Assemblies were manufactured in sizes from 3/4 - 10". The smaller 3/4 - 2" devices were produced from 1973 - 1993 and were constructed of bronze. Watts also made a hot water version of the 709 which was distinguished by the suffix "HW". Although the valve has been discontinued, a full line of repair parts are still available. The larger 2 1/2 - 10" devices began production in 1973 and are still being manufactured. The 2 1/2 - 3" valve can be ordered with bronze body or epoxy coated cast iron. the 4 - 10" devices are all epoxy coated cast iron. 2 1/2 - 10" can be ordered with a number of valve options. All models have two check covers and self contained check valves. All models have replaceable seats and require no special tools for repair.