Under normal water pressure the water filtration system will immediately visually exhibit a substantial leak if the filter cartridge is coupled to the manifold of the water filtration system in the operative position without {HEAD ~ the O ring} being positioned in {TAIL ~ the large cylindrical cavity} 
positioned in
Under normal water pressure the water filtration system will immediately visually exhibit a substantial leak if the filter cartridge is coupled to the manifold of the water filtration system in the operative position without { HEAD ~ the O ring } being positioned in { TAIL ~ the large cylindrical cavity }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL