High Pressure Part 1 Ball Valve Brass 3/4" is used to fill water tanks such as toilet cisterns. It is designed to be used in conjunction with a ball float. The ball float rises as the water rises and when a specified level is reached it causes the one way valve to be activated and shut off the water entry. The part 1 valve is straight and has the outlet on the bottom of the valve. Suitable for using in high pressure water systems and has a 3/4” connection.