Depending on the application and type of service, a wide array of DBB or DIB valve types and options are available to fit precise requirements. One example is, in liquid services close to waterways or municipalities, double-growing gate valves with DBB abilities, such as the Cameron WKM Pow-R-Seal gate valves, http://mariolvbgm.is-blog.com/203407/how-double-block-and-bleed-valve-can-save-you-time-stress-and-money