XS150 knife gate valve eliminates leakage path at the transition point between perimeter seal and chest seal. Valve features a 1-piece perimeter seal that provide bi-directional bubble tight shutoff. Seal is double-locked in the valve body, a design innovation that keeps the perimeter seal secure within its groove. Valve is an ideal solution to the common problems of performance and longevity that typically plague knife gate valves in harsh operating conditions. ITT Industries, Engineered Process Solutions Group 33 Centerville Rd., P.O. Box 6164 Lancaster, PA, 17603