The Gate Lock Valve Assembly by Posi-flate is a low cost and low maintenance alternative to the traditional rotary airlock feeder and provides a positive seal that can accommodate either full vacuum or pressure up to 6.9 bar. The air-operated seat inflates to provide a long-lasting high integrity seal and easily handles high cycling of dry granular or fine powdered materials. The seat automatically compensates for wear when it inflates against the disc, extending valve life considerably. The Posi-flate Gate Lock Assembly is available in carbon steel and stainless steel in sizes from 2 inch (50mm) to 30 inch (750mm) diameter and in any length desired. Other materials of construction are available upon request.