{HEAD ~ The aluminium foil membrane} may alternatively be reinforced by a grid structure inside {TAIL ~ the chamber} and across the inlet thereto 
{ HEAD ~ The aluminium foil membrane } may alternatively be reinforced by a grid structure inside { TAIL ~ the chamber } and across the inlet thereto
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH