a casing having {TAIL ~ a pump port}, {HEAD ~ a tank port}, and an output port, 
a casing having { TAIL ~ a pump port } , { HEAD ~ a tank port } , and an output port ,
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH