The transfer spigot has {HEAD ~ a membrane} which seals {TAIL ~ the interior} of the liner 
seals
The transfer spigot has { HEAD ~ a membrane } which seals { TAIL ~ the interior } of the liner
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH