The system effectively seals the active agent chamber and isolates it from {HEAD ~ the environment} of {TAIL ~ use} 
of
The system effectively seals the active agent chamber and isolates it from { HEAD ~ the environment } of { TAIL ~ use }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL