The slide valve includes a pre loaded spring, capable in the absence of other force of moving the slide valve to its closed position to lock {HEAD ~ the member} against {TAIL ~ movement} 
against
The slide valve includes a pre loaded spring , capable in the absence of other force of moving the slide valve to its closed position to lock { HEAD ~ the member } against { TAIL ~ movement }
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 HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL