Preferably, {HEAD ~ a duct} extends from the annular chamber into {TAIL ~ the fluid tight volume} 
extends into
Preferably , { HEAD ~ a duct } extends from the annular chamber into { TAIL ~ the fluid tight volume }
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL