As used herein a v notch ball valve is a valve in which the ball has been modified so that {TAIL ~ only a portion} of {HEAD ~ the ball} is used 
As used herein a v notch ball valve is a valve in which the ball has been modified so that { TAIL ~ only a portion } of { HEAD ~ the ball } is used
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 OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH