Self Actuating Spring Loaded Safety Relief Valve with open or closed bonnet is used for steam boilers, steam services, compressors, receivers, burners, dryers and other piping systems. Self Actuating Spring Loaded Safety Relief Valve is manufactured by Flow-tek Valves and Controls which is an ISO 9001:2000 accredited company. Flow-tek Valves and Controls also manufacture various types of valves. The Self Actuating Spring Loaded Safety Relief Valve has size ranging from 1/2 " X 3/4 " to 16" X 18". This Safety Relief Valve has screwed, flanged end.