A press block is engaged against the gasket to fully enclose an active volume between the press block, {HEAD ~ the peripheral walls} of {TAIL ~ the central opening} in the gasket, and the active surface of the substrate 
A press block is engaged against the gasket to fully enclose an active volume between the press block , { HEAD ~ the peripheral walls } of { TAIL ~ the central opening } in the gasket , and the active surface of the substrate
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 HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH