FESTO HE Series Pneumatic Manual Control Valves. HE Series control valves are designed to be small and compact with flow rates of up to 840 l/min, they offer outstanding pneumatic performance for a wide array of applications. Reliability is high as is durability due to proven piston spool valves. The series is versatile providing practical solutions to different requirements, made from reinforced PBT they are able to withstand high pressure. Featuring push-in connectors this series makes coupling and un-coupling quick and simple. Features and Benefits:. HE shut off valves, manually actuated 2/2 way bistable or 3/2 way bistable Push in connector at both ends Connection: QS-6, QS-8, QS-10, QS-12 Operating pressure -0.95 bar to 10 bar Soft sealing Piston slide design structure