The VUI series’ valves are unidirectional valves (or check valves). They allow so the flow pass free to them in a direction while, thanks to the closing of a ball, the flow is interrupted in the opposite way. The sealing of the valve, once closed, is granted thanks to a ball. Externally, a gasket avoids leakages through the threads. The check valves VUI series are available with the sizes BSPP 1/4”, 3/8”, 1/2” e 3/4”. Thanks to their compact dimensions, the employment of the check valves VUI is specially recommended in the design of HIC manifolds. The installation into specific housings with female threads allows furthermore to mounting the valves in-line. The protection against the corrosion of the external components is granted thanks to the manganese phosphating treatment.