The product titled ‘Valve Check Normally Clos 78 100CS – 415062’ is a pack of 100 check valves that are normally closed. These valves have a diameter of 7/8 inches. They are designed to allow fluid to flow through in one direction only, preventing any backflow. This pack is ideal for those who need to replace or install new valves in their system. Please note that the proper installation and maintenance of these valves are crucial for their effective operation.