A bezel and bezel assembly in which the bezel is a rigid block with a
plurality of cavities. A depression in the block has ribs extending up
therefrom to form an elevated contour. The depression includes at least
one cavity therein for the application of air pressure into the
depression and over the elevated contour. A gasket fits over the bezel so
that positive pressure applied through the at least one cavity in the
depression forces a gasket membrane to expand away from the pumping side
and negative pressure applied through the at least one cavity in the
depression pulls the gasket membrane against the elevated contour of the
ribs. The bezel may include solvent bondable tubing connections for
making pneumatic connections to the bezel.