Make of plastomer materials, strong sealing and can long terms use This kits includes necessary replacement parts to repair the bonnet and Valves assembly on model 765 backflow preventers up to 3 / 4 inch Replacing worn internals restores the preventer ' s ability to stop reverse flows and protect water sources as expected The product is precisions machined to ensures easy installation and stability during use Repairing your backflow preventer just got simpler with all the component conveniently packaged together for fast installation, Manufacturer: Zeizafa