Expansion Vessel Hose Kit including Adaptor and Service Valve Expansion Vessel Hose 3/4 inch Male to 3/4 inch Female Service Valve 3/4 inch Tesla Service Valve - Features & Benefits : Isolate without having to drain down the whole system No need to add inhibitor back into the system Allows the vessel to be isolated and drained for essential periodic servicing and re-charging Shut off and drain, for membrane expansion vessels in sealed heating and cooling systems Protected shut/open facility against inadvertent closing Anti-tamper lever Drain vessel contents according to EN 12828 Can be used in conjunction with the Tesla Sealed System Installation Kit (EVCKIT) Supplied with washer and locking wire Swivel nut for ease of installation Includes swivel drain off