In membrane filtration systems wheel-like discs with built-in connections are normally used between spiral membrane elements, both to connect the permeate tubes and to prevent membrane-telescopic movement potentially caused by the hydraulic forces exerted on the feed end. Wila ATDs benefits: - Strong design to prevent membrane-telescoping - Maximum flow area to maximise the membrane surface area available for production - Maximum opening around permeate pipe for effective membrane cleaning In recent years we have optimised the design of our stainless steel ATDs and we have eliminated any need for welding, thus making the ATDs more uniform and, most importantly, more hygienic and easier to clean. Additionally, a more rounded and open design of the connection tube makes camera inspections, if needed, much easier than on other models on the market.