In a fourth aspect of the present invention, in addition to the first aspect, the gate is connected to a portion of the groove, {TAIL ~ i.e., the portion} not forming a sealing surface of {HEAD ~ the seal} 
In a fourth aspect of the present invention , in addition to the first aspect , the gate is connected to a portion of the groove , { TAIL ~ i.e. , the portion } not forming a sealing surface of { HEAD ~ the seal }
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 TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD