The BALL-33894 2-Way High Vacuum Pneumatic Ball Valve features air-open / spring-close actuation with a NW63 port and ISO-MF flange. 2-way high vacuum ball valves are made of a body, stem, ball, and end caps. The ball is sealed within the body by end caps creating a vacuum tight central cavity. The valve is opened and closed by turning the stem 90° back and forth (1/4 turn). The sealing seat for the ball wipes the ball clean as it is opened and closed. This feature provides the “self-cleaning” action that makes this valve robust in particle-rich effluent streams.